Coffee Berry Pulp Extract Improves Hepatic Lipid Metabolism and Reduces Triglyceride Levels in High-Fat,High-Fructose Diet-Fed Mice

Abstract

This study examined the effects of coffee berry pulp (CBP) extract on hepatic lipid accumulation and blood lipid levels in mice fed on a high-fat, high-fructose (HFHF) diet. Male C57BL/6J mice were divided into the following four groups and fed their respective diets for 15 weeks: normal diet, HFHF diet, and HFHF diet supplemented with 100 or 200 mg/kg body weight CBP extract. CBP inhibited weight gain and normalized blood glucose and insulin levels. CBP supplementation also inhibited lipid and lipoprotein accumulation in the liver, thereby effectively regulating triglyceride (TG) levels in both the blood and liver. Analysis of liver lipid metabolism revealed that CBP suppressed the increased messenger RNA (mRNA) expression of sterol regulatory element-binding protein-1C induced by HFHF and downregulated both mRNA and protein levels of peroxisome proliferator-activated receptor-γ. Liver X receptor regulation occurred at the mRNA level, and the adenosine monophosphate-activated protein kinase (AMPK)/phosphorylated AMPK ratio was modulated at the protein level. Among the lipid catabolic enzymes, adipose TG lipase expression was specifically modulated by CBP treatment. These findings suggest that CBP supplementation modulates key hepatic lipid regulators and reduces blood and liver TG accumulation. Although CBP shows promise in regulating TG synthesis and storage in a mouse model, further studies, including clinical validation, are required to confirm its potential as a treatment for human non-alcoholic fatty liver disease.

Keywords

cholesterol coffee berry pulp high-fat high-fructose diet-fed mice lipid metabolism triglyceride

INTRODUCTION

Recent changes in dietary habits have increased the incidence of diseases such as metabolic disorders, which is increasing worldwide as a result of over nutrition and lack of exercise. Consequently, prevention of these metabolic diseases is more important than their treatment, thereby emphasizing the need for dietary control and exploration of functional foods.^1,2

Excess nutrients in the human body are converted into fat and stored in adipocytes or transformed into triglycerides (TGs) in the liver for storage and subsequent use.³ TGs in the blood are a representative type of lipid (fat) found in the bloodstream and adipocytes, accounting for approximately 90% of body fat. When energy is abundant, TGs are stored in adipose tissues, including under the skin or in the liver, and are broken down and used as a major energy source when needed.⁴ In the liver, fats are discharged into the bloodstream as lipoproteins and metabolized. However, excessively high TG levels in the blood can lead to hypertriglyceridemia and dyslipidemia. Moreover, these conditions are key causes of cardiovascular diseases, such as coronary artery disease, as well as diabetes, hypertension, and metabolic syndrome, thus emerging as a social issue.^4–6 Although various statin-based drugs have been developed and prescribed to improve these symptoms, side effects, such as elevated blood sugar, increased insulin resistance, and abnormal liver function, remain problematic.⁷ Therefore, prevention appears to be particularly important for improving blood TG levels and lipid metabolism. Moreover, the demand for natural substances that effectively regulate these factors with minimal side effects has increased.

Coffee berry pulp (CBP) is a major by-product of the coffee processing industry, accounting for about 45–55% of the weight of the coffee cherry.⁸ CBP has traditionally been used as a fertilizer or disposed of as environmental waste through natural decomposition⁸; however, CBP is rich in various bioactive compounds, including chlorogenic acids and caffeine.⁹ This has drawn attention to its potential as an ingredient in beverages and cosmetics, as well as its various health and environmental benefits.¹⁰

Additionally, CBP has potent antioxidant, anti-inflammatory, and antiaging effects owing to its flavonoid compounds and has the potential to serve as a therapeutic or preventive ingredient for various diseases.⁹

Therefore, this study aimed to verify the TG-lowering and lipid-metabolism-improving effects of CBP extract. Specifically, changes were monitored in liver and blood TG levels in a high-fat, high-fructose (HFHF) animal model that simulated the pathophysiology of human metabolic syndrome.

MATERIALS AND METHODS

Sample preparation

Powdered CBP extracts from Coffea arabica L. were provided by CNS Pharm Korea Co., Ltd. (Republic of Korea). The brown CBP was stored in powder form at −20°C and was dissolved in tap water at each concentration before use.

Animal studies

All animal studies were approved by the Institutional Animal Use and Care Committee of Korea University (KUIACUC-2024-0064). A group of 7-week-old male C57BL/6J mice (Orient Bio, Republic of Korea) were fed a standard laboratory diet (Orient Bio), had unlimited access to water, and were kept under a 12 hours light/dark cycle for 12 hours. Mice were treated and maintained according to the U.S. National Institutes of Health guidelines.

HFHF-induced mouse model

Mice were divided into four groups (n = 10 in each group): control (CON), negative control (NC), CBP-LOW, and CBP-HIGH. The CON group was fed the standard laboratory diet (Purina Rodent Laboratory Chow, USA). The NC group was fed a high-fat diet with 60% kcal of fat, 20% kcal of carbohydrates, and 20% kcal of protein (Research Diets Inc., New Brunswick, NJ, USA), plus 10% high-fructose (D-(-)-Fructose sc-221456B; Santa Cruz Biotechnology, Inc., Dallas, TX, USA) in their drinking water. The CBP-LOW group was fed the NC diet plus CBP (100 mg/kg body weight [BW]). The CBP-HIGH group was fed the NC diet supplemented with CBP (200 mg/kg BW). All experimental diets were administered for 15 weeks. At the end of the 15-week dietary regimen, mice were euthanized under anesthesia after fasting for 12 hours. After fasting, blood was collected from each mouse, the serum was separated and stored at −80°C until analysis. Liver tissue was extracted, rapidly frozen in liquid nitrogen, and stored at −80°C. The stored liver tissue was used for analysis of lipid parameters and biomarkers within the tissue.¹¹

Determination of blood glucose level and insulin level

Blood glucose concentrations and insulin levels were measured in the serum of HFHF-fed mice. Methodological details are provided in Supplementary Data.

Determination of TG, cholesterol, and low-density and high-density lipoprotein cholesterol levels

TG, high-density lipoprotein (HDL) cholesterol, low-density lipoprotein (LDL) cholesterol, total cholesterol (T-cholesterol), and glucose levels were measured in serum and liver of HFHF-fed mice. Methodological details are provided in Supplementary Data.

Quantitative real-time PCR analysis

Quantitative real-time PCR was performed to assess the messenger RNA (mRNA) expression of genes involved in lipid synthesis and metabolism-related factors in response to varying concentrations of CBP. Procedural details are outlined in Supplementary Data.

Western blot analysis

The effects of CBP on protein expression of lipid metabolism-related factors were confirmed using Western blotting. Detailed methods are described in Supplementary Data.

Statistical analyses

All statistical analyses were performed using Prism 8.0.2 (GraphPad Software Inc., La Jolla, CA, USA); the data are shown as means ± standard deviations (n = 10 in each group). Statistical analyses were performed using one-way analysis of variance and post-hoc Tukey’s test.

RESULTS

CBP extract is known for its efficacy in decreasing body fat; therefore, this study aimed to verify its efficacy for improving TG metabolism. CBP contains chlorogenic acid, caffeine, and antioxidants that provide various health benefits. The experiment was conducted in male C57BL/6J mice for 15 weeks, with different groups receiving different diets and CBP doses. The main findings of this study are as follows.

Changes in body and organ weights

After 15 weeks of administering a normal diet, an HFHF diet, and various CBP concentrations in combination, BW gain and final BW were evaluated (Fig. 1A, B). The HFHF diet group (NC group) showed a substantial increase of approximately 44% in both BW and organ weight gains compared to that in the normal diet group (CON group). Additionally, the CBP-treated groups exhibited BW changes and weight gain similar to those of the normal group (approximately 22% and 20% lower than those of the NC group, respectively).

FIG. 1.

Comparison of body weight (BW) changes, weight gain, liver weight, and epididymal fat weight in mice treated with CBP. (A) BW changes of mice in each group (g, weekly average). Each value represents the mean ± SD of mice in each group (n = 10 in each group). P < .001 and P > .01 versus high-fat and high-fructose alone group. (B) BW gain of mice. (C, D) Liver weight and liver weight ratio (g/BW). (E, F) Epididymal fat weight and epididymal fat ratio (g/BW). Each value represents the mean ± SD of mice in each group (n = 10 per group). ^#P < .05 versus untreated control group; *P < .05 versus high-fat and high-fructose alone group. CBP, coffee berry pulp; SD, standard deviation.

When measuring the weights of the liver and epididymal fat, the liver weight increased in the NC group compared to that in the CON group, but this increase was suppressed by CBP treatment (approximately 45% lower than that in the NC group; Fig. 1C). However, when normalized to tissue weight per gram of BW, all groups showed a decrease in liver weight compared to that in the normal group (Fig. 1D). In the case of epididymal fat, both the absolute weight and weight per gram of BW in the NC group were approximately twice as high as those in the CON group, whereas the CBP-treated group showed an increase of approximately 1.5 times that of the CON group (Fig. 1E, F).

Changes in food intake, water intake, and energy intake

After 15 weeks of dietary intervention, the daily feed intake (g) per mouse was significantly lower in the NC, LOW, and HIGH groups compared to the CON group (P < .0001). A significant difference in daily feed intake (g) per mouse was also observed between the NC and LOW groups (P < .001; Fig. 2A).

FIG. 2.

Changes in food, water, and energy intakes. Food intake (A), water intake (B), and energy intake (C) were measured every other week. Data are presented as means ± SD (n = 10 in each group). ^####P < .0001 and ^###P < .001 versus untreated control group; ***P < .001 versus high-fat and high-fructose alone group.

Additionally, daily water intake (mL) per mouse showed a similar pattern across the CON, NC, LOW, and HIGH groups during the 15-week period. The increased water intake in the second week remained similar up to the seventh week, after which it tended to decrease. There were no statistically significant differences in daily water intake (mL) per mouse among the groups (Fig. 2B).

Furthermore, the total daily energy intake (kcal) per mouse over the 15 weeks was as follows (Fig. 2C). Compared to the NC group, total caloric intake was significantly lower (P < .001) in all CON, LOW, and HIGH groups. When comparing the average total daily caloric intake per mouse over the 15 weeks for each group, the NC group (15.7 ± 0.54 kcal) had approximately 14% more intake than the CON group (10.9 ± 0.45 kcal), which was statistically significant (P < .001). In contrast, the LOW (12.0 ± 0.43 kcal) and HIGH (13.8 ± 0.47 kcal) groups showed significantly lower intake than the NC group (P < .05).

Effects of CBP on blood glucose and insulin levels

Examination of the effects of CBP on blood glucose and insulin levels revealed that both glucose and insulin levels increased in the NC group, whereas CBP treatment did not cause any notable change in glucose levels (Fig. 3A). In contrast, insulin levels were approximately four times higher in the HFHF group than in the CON group, and CBP treatment reduced these levels by approximately 50%. These findings suggest that CBP treatment influences insulin regulation (Fig. 3B).

FIG. 3.

Effect of CBP on serum glucose and insulin levels in the livers of mice fed a high-fat and high-fructose diet. (A) Blood glucose levels. (B) Blood insulin levels. Values are presented as means ± SD for each group of mice (n = 10 per group). ^#P < .05 versus untreated control group; *P < .05 versus high-fat and high-fructose alone group.

Effects of CBP on lipid and lipoprotein levels in blood and liver

To investigate the effects of CBP on lipid metabolism, T-cholesterol, TG, HDL cholesterol, and LDL cholesterol levels were measured in blood and liver samples (Fig. 4). For T-cholesterol, the HFHF group showed an overall increase of approximately 50% or even double in both the blood and liver compared to that in the CON group, whereas the cholesterol-lowering effect of CBP was minimal. Moreover, HFHF administration resulted in a TG increase of approximately 50% (in the blood) and 100% (in the liver), and TG levels decreased considerably in a dose-dependent manner after CBP treatment (25–50% decrease compared with that of NC). Among the lipoproteins, HDL levels increased in both the blood and liver following CBP treatment, whereas LDL levels tended to decrease in the liver.

FIG. 4.

Effect of CBP on lipid and lipoprotein profiles in the livers of mice fed an HFHF diet. (A–D) Changes in lipid and lipoprotein levels in the serum. (E–H) Changes in lipid and lipoprotein levels in the liver. Values are presented as means ± SD for each group of mice (n = 10 per group). ^#P < .05 versus untreated control group; *P < .05 versus high-fat and high-fructose alone group. HFHF, high-fat, high-fructose.

Effects of CBP on the expression of lipid metabolism-related biomarkers in the liver

The regulation of TG, HDL, and LDL cholesterol levels following CBP administration in the liver and blood was verified, and biomarkers related to these factors were measured to determine the mechanism underlying the efficacy of CBP (Fig. 5). When examining the mRNA expression of Srebp-1c, Fasn, and Scd-1, which are involved in lipogenesis, Srebp-1c mRNA expression decreased by approximately 20% in the CBP-LOW (100 mg/kg BW) group compared to that in the HFHF group, whereas the expression in the CBP-HIGH (200 mg/kg BW) group was similar to that of the NC group. The effects of CBP and HFHF on Fasn and Scd-1mRNA expressions were minor. In terms of Lxr and Ppar-γ, which are associated with lipid metabolism, administration of HFHF increased mRNA expression (approximately twofold or 25% higher than that of the CON group), and this expression was suppressed by CBP, especially in the CBP-HIGH (200 mg/kg BW) group.

FIG. 5.

Effect of CBP on gene expression of Srebp-1c, Fasn, Scd-1, Lxr and Ppar-γ involved in lipid metabolism in mouse liver after HFHF-diet administration. Values are presented as means ± SD for each group of mice (n = 10 per group). ^#P < .05 versus untreated control group; *P < .05 versus high-fat and high-fructose alone group.

The protein expression levels of Srebp-1C, Fas, Cd36, Ppar-γ, and p-Ampk/Ampk were also confirmed (Fig. 6). Similar to the mRNA expression results, sterol regulatory element-binding protein-1C (SREBP-1C) levels increased with HFHF administration (approximately 2.5 times higher than those in the CON group); however, a reducing effect of CBP treatment was not observed. Additionally, Fas, which is influenced by Srebp-1C, tended to increase with the HFHF diet and decrease with low-dose CBP, but the difference was not statistically significant.

FIG. 6.

Effects of CBP on the protein expression of lipid metabolism-related biomarkers in the livers of mice fed HFHF diet. (A) Western blotting bands. (B) Protein levels of Srebp-1c, Fas, Cd36, and Ppar-γ were normalized to Gapdh or α-tubulin, whereas p-Ampk was normalized to total Ampk, followed by densitometric quantification. Values are presented as means ± SD for each group of mice (n = 10 per group). ^#P < .05 versus untreated control group; *P < .05 versus high-fat and high-fructose alone group.

Furthermore, the protein expression of CD36, a factor involved in SREBP-1C activation and hepatic fatty acid transport, increased following HFHF administration and was suppressed by CBP. Peroxisome proliferator-activated receptor-γ (PPAR-γ) is involved in early lipid synthesis and adipocyte differentiation, and its protein expression was markedly increased by HFHF (approximately 50% higher than that in the CON group), which was similar to the mRNA results. Furthermore, PPAR-γ protein expression decreased substantially in proportion with the CBP dose, with the CBP-HIGH (200 mg/kg BW) group showing a pronounced decrease (approximately 53% compared to that in the NC group). Adenosine monophosphate-activated protein kinase (AMPK) is an energy metabolism sensor, and when its activated form (p-AMPK) is increased, fatty acid oxidation increases, and lipogenesis is suppressed. Based on p-AMPK/AMPK measurements, HFHF administration reduced AMPK activity, whereas CBP treatment increased its activity. In particular, the CBP-LOW group (100 mg/kg) exhibited an increase in the p-AMPK/AMPK ratio.

Effects of CBP on the expression of lipolytic factors in the liver

The expression of biomarkers related to lipid metabolism in the liver was measured and compared at both the mRNA and protein levels. Compared to biomarkers related to SREBP-1C, CBP appeared to have a regulatory effect on PPAR-γ. Therefore, the expression of adipose TG lipase (Atgl), hormone-sensitive lipase (Hsl), and monoglyceride lipase (Mgl), which are lipolytic enzymes associated with PPAR-γ activity, was examined at the mRNA level (Fig. 7). The HFHF diet decreased Atgl mRNA expression (approximately 40% decrease compared to that in the CON group) and tended to increase slightly with CBP treatment (approximately 30% increase compared to that in the NC group). Hsl expression tended to increase with the HFHF diet and was downregulated by CBP; however, no significant difference in its expression was observed. For Mgl, a highly pronounced increase in mRNA expression was observed following HFHF administration (approximately 20-fold compared to that in the CON group), which was markedly downregulated by CBP treatment (70–80% decrease compared to that in NC group). Collectively, these results suggest that CBP affects the expression of lipolytic enzymes.

FIG. 7.

Effect of CBP on the gene expression of Atgl, Hsl, and Mgl in the livers of mice fed HFHF diet. Values are presented as means ± SD for each group of mice (n = 10 per group). ^#P < .05 versus untreated control group; *P < .05 versus high-fat and high-fructose alone group.

DISCUSSION

This study evaluated the effects of CBP extract on improving TG levels and lipid metabolism in vivo. CBP contains chlorogenic acid, caffeine, and various antioxidants and exhibits a range of physiological activities owing to these active components.^12,13 This study targeted an HFHF-induced mouse model that mimics the conditions of lipid metabolic abnormalities and non-alcoholic fatty liver disease (NAFLD) in humans.¹⁴ This model allows for the study of the combined effects of high-fat and high-fructose intake, which is a crucial factor in the development of NAFLD in humans.¹⁵

The efficacy was evaluated by administering various concentrations of CBP extract along with an HFHF diet to male C57BL/6J mice for 15 weeks. The HFHF diet disrupts hepatic lipid metabolism and induces fat accumulation in the liver, thereby contributing to the pathogenesis of NAFLD.¹⁶ Furthermore, an HFHF diet leads to a more severe accumulation of hepatic TGs than a high-fat or high-fructose diet alone.¹⁶ Mice fed an HFHF diet for 4–12 weeks exhibit microvesicular and macrovesicular steatosis in the liver. In severe cases, features of metabolic diseases, such as NAFLD, progression to liver fibrosis, and insulin resistance, are also observed, rendering this a widely used disease model for TG-related research.¹⁷ In this study, administration of an HFHF diet increased TG levels in the blood and liver, elevated cholesterol and LDL cholesterol levels, and decreased HDL cholesterol levels. After 15 weeks of CBP extract administration, substantial reductions in TG, LDL cholesterol, and T-cholesterol levels were observed in the liver and blood of the mice. Under normal conditions, TGs and cholesterol maintain a balance between their synthesis and breakdown within tissues, and blood lipoprotein concentrations are regulated by homeostasis. However, genetic or environmental factors that disrupt lipid metabolism can cause a sharp increase in TG levels, elevate plasma LDL levels, and decrease HDL cholesterol levels, thereby increasing the risk of various metabolic disorders, such as hypertension, atherosclerosis, and fatty liver disease.^18,19

To evaluate the effects of CBP on abnormal lipid metabolism, TG levels in the liver and blood were measured. In the HFHF diet group, TGs increased markedly compared to other cholesterol types. CBP administration substantially inhibited the increase in TG levels, which were higher than those of other lipids. TGs are primarily synthesized in the liver and are important metabolic products that supply energy to various tissues, except the brain and red blood cells.²⁰ However, when TGs accumulate excessively in the liver, LDL cholesterol synthesis also increases, leading to elevated concentrations of TGs and LDL cholesterol in the blood and a subsequent risk of atherosclerosis.²⁰

Based on these results, the molecular mechanisms by which CBP affects the accumulation or synthesis of TGs and fats in the liver and blood were examined at the mRNA and protein levels.

The mRNA and protein expression of lipid metabolism-related genes, such as LXR, SREBP-1, FAS, PPAR-γ, SCD-1, and CD36, showed that mRNA and protein expression of LXR, SREBP-1, SCD-1, and CD36 were considerably increased in the HFHF diet group. LXR is a transcription factor involved in cholesterol and fatty acid synthesis that promotes the expression of SREBP-1. When LXR expression decreases, the expression of SREBP-1 and fatty acid synthesis also decreases, thereby inhibiting the accumulation of TGs in the liver.^21,22 In this study, the HFHF diet led to increased expression of LXR and SREBP-1C, which are involved in lipid synthesis, and consequently induced SCD-1 and ACC activation. This promoted the generation of lipids, including TGs, which is consistent with previous reports.²³ However, in the case of FAS, the difference in expression was not statistically significant.

When PPAR-γ is activated in the liver, the expression of genes involved in fat storage and insulin sensitivity increases, resulting in enhanced fat synthesis and accumulation within the liver.²⁴ Additionally, overexpression of lipid synthesis-related factors, such as PPAR-γ, SREBP-1c, and CD36, promotes the synthesis of fatty acids in the liver and leads to an excessive influx of fatty acids from the blood into liver cells. This causes over-activation of TG and lipid synthesis within hepatocytes and increases the accumulation of TGs, cholesterol, and similar substances.²⁴ CBP administration appears to regulate the expression of lipid synthesis regulatory factors, thereby reducing cholesterol, TG, and lipoprotein levels in the liver and blood.

In particular, CBP suppressed the expression of PPAR-γ and CD36 in the liver compared to other factors. This regulatory effect of CBP on PPAR-γ and CD36 expression appears to reduce TG and lipid levels in the liver and blood by inhibiting hepatic lipid synthesis and controlling the intracellular fatty acid uptake. Furthermore, the HFHF diet increased lipid and lipoprotein levels in the liver and blood; among these, CBP treatment markedly suppressed the increase in TGs compared to other lipids. This suggests that the active components within CBP extract (caffeic acid, chlorogenic acid, and epicatechin) regulate the activity of LXR/SREBP-1/PPAR-γ, promote the phosphorylation of AMPK, and thereby inhibit lipid synthesis and promote fatty acid oxidation. This reduces TGs and lipid levels in the liver and blood.²⁵

Results confirmed that the expression of biomarkers related to lipid metabolism such as SREBP-1C, AMPK, and PPAR-γ is regulated by CBP treatment. Most biomarkers showed regulatory changes proportional to the increase in CBP dosage. However, in the case of SREBP-1C inhibition and AMPK activation, more favorable effects were observed with a low dose (100 mg/kg BW) compared to a high dose (200 mg/kg BW). Similar findings have been reported in studies of other natural substances, where the efficacy does not tend to increase in a concentration-dependent manner when low and high doses are administered in animal models of metabolic disorders or obesity, similar to this study.^26,27 This is thought to be due to a hormesis mechanism or biphasic dose-response, whereby certain active minor components in the natural extract sufficiently affect AMPK-SREBP-1C activation at low concentrations, but at higher concentrations, the effect is no longer apparent or even inhibited.^28,29

CBP reduced TG levels; thus, the expression of Atgl, Hsl, and Mgl, all of which are associated with TG metabolism, was examined. ATGL plays an important role in fatty liver disease (metabolic dysfunction-associated steatotic liver disease/NAFLD) by hydrolyzing TGs and releasing free fatty acids that can accumulate in the liver.^30,31 Although the expression of HSL in liver tissue is low or not considerably changed, an HSL decrease or deficiency leads to a fatty liver, reduced hepatic TG breakdown, and decreased metabolic activities, such as fatty acid oxidation and very low density lipoprotein synthesis.³¹ Additionally, when the expression or activity of MGL, which breaks down monoacylglycerol in the liver to produce fatty acids, is increased, fatty liver often develops. This influences the re-release of fatty acids and fat accumulation.^32,33 In this study, Atgl and Mgl expression was abnormally regulated by HFHF treatment, and this abnormal regulation was improved by CBP treatment. This is thought to be regulated by the phytochemicals present in CBP.³⁴

CONCLUSION

CBP extract was administered for 15 weeks to C57/BL6 mice fed an HFHF diet to induce TG elevation. This treatment comprehensively reduced TGs in the liver and blood and improved lipid metabolism. In particular, the decrease in TG levels in the liver and blood was associated with inhibition of SREBP-1c, LXR, PPAR-γ, and CD36 activity and enhancement of AMPK activity by CBP. This suppressed fatty acid synthesis and oxidation, thereby influencing the synthesis and breakdown of TGs and lipids. Notably, CBP effectively regulated liver and blood TG levels, which appear to be related to the regulation of LXR/PPAR-γ/CD36 signaling and ATGL and MGL, which are associated with fatty acid degradation. Based on a comprehensive review of the results of this study, although some biomarker analyses indicate that the effective dose is 100 mg/kg BW in mice, reviewing the analyses of cholesterol, TG, lipoprotein, and other related biomarkers for lipid metabolism in blood and liver suggests that the optimal effective dose is 200 mg/kg BW in mice. When these dosages are converted for humans,³⁵ 100 mg/kg BW (mice) becomes 8.11 mg/kg BW (human), and 200 mg/kg BW (mice) becomes 16.22 mg/kg BW (human). These research findings demonstrate that CBP has promising potential for regulating TG synthesis and storage in the blood and liver; however, additional studies on pharmacokinetics and metabolism are considered necessary for developing functional ingredients or new drug candidates to control human NAFLD.

AUTHORS’ CONTRIBUTIONS

B.K.H. and Y.J.K.: Writing—review and editing and Supervision. M.J.K.: Conceptualization (lead), investigation (lead), writing—original draft (lead), and writing—review and editing (equal). S.B.L.: Methodology, investigation (support), and writing—original draft (support). D.G.P. and H.-H.J.: Methodology (leads). J.Y.H.: Validation (lead) and formal analysis (support). J.-I.K.: Validation (support) and formal analysis (support). S.Y.P.: Methodology (lead) and writing—review and editing.

Footnotes

AUTHOR DISCLOSURE STATEMENT

The authors declare no conflicts of interest.

FUNDING INFORMATION

This work was supported by the Health Functional Food R&D Program (RS-2022-00167221), funded by the Ministry of SMEs and Startups (Korea).

Supplemental Material

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