Combinatory effects of phytoestrogens and exercise on body fat mass and lipid metabolism in ovariectomized female rats

Combination of ferulic acid and exercise alleviates menopause symptoms and skin remodeling in ovariectomized rats

BACKGROUND/OBJECTIVES

Estrogen regulates certain biological functions, including bone health, maintenance of skin components, and cardiovascular and brain protection. Estrogen deficiency manifests as hot flashes, wrinkles, skin dryness, reduced bone mineral density (BMD), sleep disorders, and cardiovascular diseases. This study aimed to investigate the effects of aerobic exercise combined with ferulic acid (FA) in ovariectomized rats.

MATERIALS/METHODS

Female Sprague-Dawley rats were classified into control (N), ovariectomy (OV), ovariectomy and exercise (OV+EX), and ovariectomy and exercise with ferulic acid (OV+EX+F) groups. Following ovariectomy at 22 weeks of age, the rats were tower climbing exercise at gradually increase the load (3 days/week for 12 weeks) with or without FA (5 g/kg diet) administration.

RESULTS

Estrogen deficiency in female rats (OV group) resulted in increased body weight, increased blood triglyceride (TG) levels, and decreased BMD following ovariectomy. Interestingly, compared with the rats in the OV group, the rats in the OV+EX+F group exhibited reduced body weight and blood TG levels and maintained BMD following ovariectomy, similar to those in the N group. Histological analysis of the skin of estrogen-deficient rats (OV group) revealed significantly decreased skin thickness with fewer dermal cells and distorted subcutaneous fat layers, similar to the aging phenotype. Interestingly, the rats in the OV+EX+F group exhibited rescued skin phenotypes compared with those in the OV and OV+EX groups. The skin of rats from all groups was analyzed for the expression of DNA damage and repair proteins. The OV+EX+F and OV+EX groups exhibited enhanced protein levels of pCHK1 (S345), an initiator of DNA repair signaling, and p53, indicating increased cellular DNA damage because of ovariectomy and ultimately an underlying DNA repair process.

CONCLUSION

Exercise with FA had beneficial effects on lipid profiles, BMD, and skin remodeling during menopause.

Milk fat globule membranes ameliorate diet-induced obesity in mice by modulating glucolipid metabolism, body inflammation, and oxidative stress

This study aimed to explore the lipid-lowering effect and the mechanism of action of the milk fat globule membrane (MFGM) in obese mice. All findings indicated that MFGM supplementation impeded weight gain in mice with obesity. qPCR and western blot analysis further revealed that MFGM could reduce lipid deposition and improve lipid metabolism by downregulating the expression levels of Fas, Scd1, PPARγ, and Srebp-1c and increasing the expression levels of Mcad, Cpt-1c, and PPAR-α. MFGM also reduced glucose metabolism disorders by downregulating the expression levels of Pepck and G6pase and upregulating the expression levels of PK and GK. MFGM can reduce the expression levels of TNF-α, IL-6, and IL-1β, thus reducing inflammation in the body. In addition, MFGM also increased the expression of the Nrf2 gene, strengthening the antioxidant enzymes' (GSH, CAT, and SOD) vitality, which strengthened the body's defenses against oxidative stress. In summary, our experiment demonstrated that the MFGM has the potential to treat obesity by controlling the metabolism of fat and glucose, thereby reducing oxidative stress and inflammation, which provides a theoretical foundation for the development of products related to the treatment of obesity.

Protective effect of phytoestrogens on nonalcoholic fatty liver disease in postmenopausal women

Non-alcoholic fatty liver disease (NAFLD) is a progressive metabolic disease characterized by hepatic steatosis, inflammation, and fibrosis that seriously endangers global public health. Epidemiological studies have shown that the incidence of non-alcoholic fatty liver disease in postmenopausal women has significantly increased. Studies have shown that estrogen deficiency is the main reason for this situation, and supplementing estrogen has become a new direction for preventing the occurrence of postmenopausal fatty liver. However, although classical estrogen replacement therapy can reduce the incidence of postmenopausal NAFLD, it has the risk of increasing stroke and cardiovascular diseases, so it is not suitable for the treatment of postmenopausal NAFLD. More and more recent studies have provided evidence that phytoestrogens are a promising method for the treatment of postmenopausal NAFLD. However, the mechanism of phytoestrogens in preventing and treating postmenopausal NAFLD is still unclear. This paper summarizes the clinical and basic research evidence of phytoestrogens and reviews the potential therapeutic effects of phytoestrogens in postmenopausal NAFLD from six angles: enhancing lipid metabolism in liver and adipose tissue, enhancing glucose metabolism, reducing oxidative stress, reducing the inflammatory response, regulating intestinal flora, and blocking liver fibrosis (Graphical Abstract).

Chinese chestnut shell polyphenol extract regulates the JAK2/STAT3 pathway to alleviate high-fat diet-induced, leptin-resistant obesity in mice

Chinese chestnut shell is a by-product of chestnut food processing and is rich in polyphenols. This study sought to investigate the effect of chestnut shell polyphenol extract (CSP) on weight loss and lipid reduction in a 12-week high-fat diet (HFD)-induced murine obesity model. CSP (300 mg per kg body weight) was administered intragastrically daily. AG490, a JAK2 protein tyrosine kinase inhibitor, was also intraperitoneally injected. The results showed that an HFD induced leptin resistance (LR). Compared to corresponding values in the HFD group, CSP treatment improved blood lipid levels, weight, and leptin levels in obese mice (p < 0.01). Additionally, CSP treatment enhanced enzyme activity by improving total antioxidant capacity, attenuating oxidative stress, and reducing fat droplet accumulation and inflammation in the liver, epididymal, and retroperitoneal adipose tissue. CSP also activated the LEPR-JAK2/STAT3-PTP1B-SOCS-3 signal transduction pathway in hypothalamus tissue and improved LR while regulating the expression of proteins related to lipid metabolism (PPARγ, FAS, and LPL) in white adipose tissue in the retroperitoneal cavity. However, the amelioration of lipid metabolism by CSP was dependent on JAK2. Molecular docking simulation further demonstrated the strong binding affinity of procyanidin C1 (-10.3983297 kcal mol^-1) and procyanidin B1 (-9.12686729 kcal mol^-1) to the crystal structure of JAK2. These results suggest that CSP may be used to reduce HFD-induced obesity with potential application as a functional food additive.

Adipose tissue and ovarian aging: Potential mechanism and protective strategies

Ovarian aging occurs approximately 10 years prior to the natural age-associated functional decline of other organ systems. With the increase of life expectancy worldwide, ovarian aging has gradually become a key health problem among women. Therefore, understanding the causes and molecular mechanisms of ovarian aging is very essential for the inhibition of age-related diseases and the promotion of health and longevity in women. Recently, studies have revealed an association between adipose tissue (AT) and ovarian aging. Alterations in the function and quantity of AT have profound consequences on ovarian function because AT is central for follicular development, lipid metabolism, and hormonal regulation. Moreover, the interplay between AT and the ovary is bidirectional, with ovary-derived signals directly affecting AT biology. In this review, we summarize the current knowledge of the complex molecular mechanisms controlling the crosstalk between the AT and ovarian aging, and further discuss how therapeutic targeting of the AT can delay ovarian aging.

Estrogen receptor α activation modulates the gut microbiome and type 2 diabetes risk factors

Estradiol and exercise can decrease risk factors associated with type 2 diabetes (T2D) including total body weight gain and abdominal fat gain. Estradiol functions through estrogen receptor (ER) α and ERβ. Some studies suggest that activation of ERα may provide protection against T2D. Female Wistar rats were ovariectomized and fed a high-fat diet for 10 weeks and divided into the following 5 experimental groups: (1) no treatment (control), (2) exercise, (3) estradiol, (4) propylpyrazoletriyl (a selective ERα agonist), and (5) diarylpropionitrile (a selective ERβ agonist). ERα activation decreased the abundance of Firmicutes, and ERα and ERβ activation increased the abundance of Bacteroidetes. ERα activation decreased food consumption, and ERα and ERβ activation increased voluntary activity. Exercise was the only treatment to decrease the blood glucose and serum insulin levels. ERα activation, but not ERβ, increased hepatic protein expression of ACC and FAS and decreased hepatic protein expression of LPL. ERα activation also decreased hepatic mRNA expression of PPARα and PPARγ. This study elucidates the functions of estradiol by assessing specific activation of ERα and ERβ. As obesity increases the abundance of Firmicutes and decreases the abundance of Bacteroidetes, our study shows that ERα activation can restore the gut microbiome to non-obese abundances. This study further provides novel insights into ERα's role in hepatic fat metabolism via regulation of ACC, FAS, LPL, PPARα, and PPARγ.

The advantages of physical exercise as a preventive strategy against NAFLD in postmenopausal women

BACKGROUND

The prevalence and severity of nonalcoholic fatty liver disease (NAFLD) increase in women after menopause. This narrative review discusses the causes and consequences of NAFLD in postmenopausal women and describes how physical activity can contribute to its prevention.

METHODS

The authors followed the narrative review method to perform a critical and objective analysis of the current knowledge on the topic. The Medical Subject Heading keywords 'physical exercise', 'menopause', 'hormone replacement therapy', 'estradiol' and 'NAFLD' were used to establish a conceptual framework. The databases used to collect relevant references included Medline and specialized high-impact journals.

RESULTS

Higher visceral adiposity, higher rate of lipolysis in adipose tissue after oestrogen drop and changes in the expression of housekeeping proteins involved in hepatic lipid management are observed in women after menopause, contributing to NAFLD. Excessive liver steatosis leads to hepatic insulin resistance, oxidative stress and inflammation, accelerating NAFLD progression. Physical activity brings beneficial effects against several postmenopausal-associated complications, including NAFLD progression. Aerobic and resistance exercises partially counteract alterations induced by metabolic syndrome in sedentary postmenopausal women, impacting NAFLD progression and severity.

CONCLUSIONS

With the increased global obesity epidemic in developing countries, NAFLD is becoming a severe problem with increased prevalence in women after menopause. Evidence shows that physical activity may delay NAFLD development and severity in postmenopausal women, although the prescription of age-appropriate physical activity programmes is advisable to assure the health benefits.

Effect of 12-wk Training in Ovariectomised Rats on PGC-1α, NRF-1 and Energy Substrates

Metabolic diseases are associated with hypoestrogenism owing to their lower energy expenditure and consequent imbalance. Physical training promotes energy expenditure through PGC-1α and NRF-1, which are muscle proteins of the oxidative metabolism. However, the influence of physical training on protein expression in individuals with hypoestrogenism remains uncertain. Thus, the aim of this study is to determine the effect of 12 weeks of moderate-intensity swimming training on the muscle expression of PGC-1α, NRF-1, glycogen and triglyceride in ovariectomised rats. OVX and OVX+TR rats were subjected to ovariectomy. The trained animals swam for 30 minutes, 5 days/week, at 80% of the critical load intensity. Soleus was collected to quantify PGC-1α and NRF-1 expressions, while gastrocnemius and gluteus maximus were collected to measure glycogen and triglyceride. Blood glucose was also evaluated. Whereas ovariectomy decreased PGC-1α expression (p<0.05) without altering NRF-1 (p=0.48), physical training increased PGC-1α (p<0.01) and NRF-1 (p<0.05). Ovariectomy reduced glycogen (p<0.05) and triglyceride (p<0.05), whereas physical training increased glycogen (p<0.05) but did not change triglyceride (p=0.06). Ovariectomy increased blood glucose (p<0.01), while physical training reduced it (p<0.01). In summary, 12 weeks of individualized and moderate-intensity training were capable of preventing muscle metabolic consequences caused by ovariectomy.

Genistein Regulates Lipid Metabolism via Estrogen Receptor β and Its Downstream Signal Akt/mTOR in HepG2 Cells

Genistein (GEN) has been shown to significantly inhibit hepatic triglyceride accretion triggered by estrogen deficiency. The main purpose of this in vitro study was to investigate the function and molecular mechanism of estrogen receptor β (ERβ) in regulating hepatic lipid metabolism induced by GEN. Different doses of GEN or GEN with an ERβ antagonist were treated with HepG2 cells. Results showed that 25 μM GEN significantly diminished triglyceride levels. Meanwhile, GEN downregulated the levels of genes and proteins involved in lipogenesis, such as sterol-regulatory element-binding protein-1c (SREBP-1c), fatty acid synthase (FASN), and stearoyl-coenzyme A desaturase 1 (SCD1), and upregulated the gene and protein levels of the regulation factors responsible for fatty acid β-oxidation, such as carnitine palmitoyltransferase 1α (CPT-1α) and peroxisome proliferator-activated receptor α (PPARα). Furthermore, 25 μM GEN reduced the levels of phosphorylation of protein kinase B (Akt) and mechanistic target of rapamycin (mTOR). Moreover, most of these effects from GEN were reverted by pretreatment with the antagonist of ERβ. In conclusion, GEN improved hepatic lipid metabolism by activating ERβ and further modulation of Akt/mTOR signals. The results provide novel aspects of the regulatory mechanism of ERβ on hepatic lipid metabolism and might help to profoundly understand the functions of food-derived phytoestrogens in preventing and treating hepatic steatosis in postmenopausal women.

Soy Isoflavones Intake and Obesity in Chinese Adults: A Cross-Sectional Study in Shanghai, China

This study was designed to examine the association of soy isoflavones (SI) intake with different body measurements indicative of obesity in Chinese adults of Shanghai, a population consuming foods rich in SI. This study used baseline data from the Shanghai Gaofeng cohort study. SI intake was measured by using a self-reported food frequency questionnaire (FFQ). A restricted cubic spline (RCS) was performed to examine the possible nonlinear relationship of SI intake with obesity. A logistic regression model was applied to estimate the odds ratios (OR) and 95% confidence interval (CI). Compared with the lowest tertile group of SI intake, the highest tertile group had a lower prevalence of obesity and central obesity. The OR for overall obesity was 0.91 (95% CI: 0.85, 0.98) in the highest versus the lowest SI tertile group; the associations differed by sex and menopausal status. A negative association was also observed between SI intake and central obesity, and a significant modifying effect of sex was found on the association. No significant interactions were observed between SI intake and physical activity (PA) levels. Our results suggest that Chinese adults with higher dietary intake of SI may be less likely to be obese, particularly for postmenopausal women.

Puerarin ameliorated pressure overload-induced cardiac hypertrophy in ovariectomized rats through activation of the PPARα/PGC-1 pathway

Estrogen deficiency induces cardiac dysfunction and increases the risk of cardiovascular disease in postmenopausal women and in those who underwent bilateral oophorectomy. Previous evidence suggests that puerarin, a phytoestrogen, exerts beneficial effects on cardiac function in patients with cardiac hypertrophy. In this study, we investigated whether puerarin could prevent cardiac hypertrophy and remodeling in ovariectomized, aortic-banded rats. Female SD rats subjected to bilateral ovariectomy (OVX) plus abdominal aortic constriction (AAC). The rats were treated with puerarin (50 mg·kg-1 ·d-1, ip) for 8 weeks. Then echocardiography was assessed, and the rats were sacrificed, their heart tissues were extracted and allocated for further experiments. We showed that puerarin administration significantly attenuated cardiac hypertrophy and remodeling in AAC-treated OVX rats, which could be attributed to activation of PPARα/PPARγ coactivator-1 (PGC-1) pathway. Puerarin administration significantly increased the expression of estrogen-related receptor α, nuclear respiratory factor 1, and mitochondrial transcription factor A in hearts. Moreover, puerarin administration regulated the expression of metabolic genes in AAC-treated OVX rats. Hypertrophic changes could be induced in neonatal rat cardiomyocytes (NRCM) in vitro by treatment with angiotensin II (Ang II, 1 μM), which was attenuated by co-treatemnt with puerarin (100 μM). We further showed that puerarin decreased Ang II-induced accumulation of non-esterified fatty acids (NEFAs) and deletion of ATP, attenuated the Ang II-induced dissipation of the mitochondrial membrane potential, and improved the mitochondrial dysfunction in NRCM. Furthermore, addition of PPARα antagonist GW6471 (10 μM) partially abolished the anti-hypertrophic effects and metabolic effects of puerarin in NRCM. In conclusion, puerarin prevents cardiac hypertrophy in AAC-treated OVX rats through activation of PPARα/PGC-1 pathway and regulation of energy metabolism remodeling. This may provide a new approach to prevent the development of heart failure in postmenopausal women.

Daidzein stimulates fatty acid-induced fat deposition in C2C12 myoblast cells via the G protein-coupled receptor 30 pathway

Fat deposition in skeletal muscle is an important aspect of improving meat quality. Isoflavones can promote animal anabolism, but whether and how they regulate muscle fat deposition remain largely unclear. In this study, we explored the role and corresponding molecular mechanism of one of the major isoflavones, daidzein, in fat deposition in C2C12 myoblast cells. In the absence of fatty acids (FAs), daidzein did not promote triglyceride synthesis and lipid droplet formation in cells but increased sterol regulatory element-binding protein 1c (SREBP-1c) expression and maturation. In the presence of FAs, daidzein enhanced FAs-induced fat deposition and the SREBP-1c signaling. Daidzein promoted FAs-induced nuclear factor κB1 (NFκB1) phosphorylation and activated the SREBP-1c signaling in a PI3K-dependent manner. G protein-coupled receptor 30 (GPR30) knockdown but not estrogen receptor α (ERα) knockdown blocked the stimulation of daidzein on the PI3K-NFκB1-SREBP-1c signaling pathway, while both knockdown did not affect the stimulation of FAs on this signaling. qRT-PCR and ChIP-qPCR further detected that daidzein stimulated NFκB1-targeted SREBP-1c transcription. Daidzein did not affect ERα expression in cells, but it stimulated GPR30 expression and cytoplasmic localization. These results reveal that daidzein promotes FAs-induced fat deposition through the GPR30 signaling in C2C12 myoblast cells.

Exercise and/or Genistein Treatment Impact Gut Microbiota and Inflammation after 12 Weeks on a High-Fat, High-Sugar Diet in C57BL/6 Mice

Genistein (Gen) and exercise (Exe) have been postulated as potential strategies to ameliorate obesity, inflammation, and gut microbiota (GM) with promising results. However, the impact of the combination of both Exe and Gen is yet to be investigated. We aimed to analyze the impacts of Exe, Gen, and their combined effects on GM and inflammation in mice after a 12-week high-fat, high-sugar diet (HFD). Eighty-three C57BL/6 mice were randomized to control, HFD, HFD + Exe, HFD + Gen, or HFD + Exe + Gen. The V4 region of the 16S rRNA gene was analyzed with Illumina MiSeq. Serum samples were used to analyze interleukin (Il)-6 and Tumor Necrosis Factor alpha (TNF-alpha). The HFD + Exe and HFD + Exe + Gen treatments resulted in significantly greater microbial richness compared to HFD. All the treatments had a significantly different impact on the GM community structure. Ruminococcus was significantly more abundant after the HFD + Exe + Gen treatment when compared to all the other HFD groups. Exe + Gen resulted in serum Il-6 concentrations similar to that of controls. TNF-alpha concentrations did not differ by treatment. Overall, Exe had a positive impact on microbial richness, and Ruminococcus might be the driving bacteria for the GM structure differences. Exe + Gen may be an effective treatment for preventing HFD-induced inflammation.

PPARGC1A gene polymorphism is associated with exercise-induced fat loss

Obesity is a widespread problem within modern society, serving to increase the risk of cardiovascular, metabolic, and neurodegenerative disorders. Peroxisome proliferator-activated receptor gamma (PPARγ) and PPARγ coactivator 1 α (PGC1α) play a key role in the regulation of cellular energy metabolism and is implicated in the pathology of these diseases. This study examined the association between polymorphisms of the PPARG and PPARGC1A genes and individual variability in weight loss in response to physical activity intervention. 39 obese Ukrainian women (44.4 ± 7.5 years, BMI > 30.0 kg/m²) undertook a 3-month fitness program whilst following a hypocaloric diet (~ 1500 cal). Anthropometric and biochemical measurements took place before and after the program. Single nucleotide polymorphisms within or near PPARG (n = 94) and PPARGC1A (n = 138) were identified and expression of PPARG mRNA was measured via reverse transcription and amplification. The association between DNA polymorphisms and exercise-induced weight loss, initial body mass, biochemistry and PPARG expression was determined using one-way analysis of variance (ANOVA). The present intervention induced significant fat loss in all participants (total fat: 40.3 ± 5.3 vs 36.4 ± 5.7%; P < 0.00001). Only one polymorphism (rs17650401 C/T) within the PPARGC1A gene was found to be associated with fat loss efficiency after correction for multiple testing, with T allele carriers showing the greatest reduction in body fat percentage (2.5-fold; P = 0.00013) compared to non-carriers. PPARGC1A (rs17650401) is associated with fat loss efficiency of the fitness program in obese women. Further studies are warranted to test whether this variation is associated with fat oxidation.

Moderate intensity intermittent exercise upregulates neurotrophic and neuroprotective genes expression and inhibits Purkinje cell loss in the cerebellum of ovariectomized rats

Decreases in estrogen levels due to menopause or ovariectomy may disrupt cerebellar motor functions. This study aimed at investigating the effects of Moderate Intensity Intermittent Exercise (MIEx) on the cerebellum of ovariectomized rats by analyzing neurotrophic and neuroprotective markers, as well as cerebellar motor functions. Thirty-two female Sprague Dawley rats were divided into four groups, i.e. Sham and ovariectomy (Ovx) of non-MIEx (NMIEx) groups, and Sham and Ovx with MIEx groups. MIEx was performed 5 days a week on treadmill for 6 weeks. Motor functions were assessed using rotarod, footprint, open field, and wire hanging tests. Real-time polymerase chain reaction was performed to determine messenger RNA (mRNA) expressions of Pgc-1α, BDNF, synaptophysin, Bcl-2, and Bax. Unbiased stereology was used to estimate the total number of cerebellar Purkinje cells. The Ovx MIEx group had higher Pgc-1α and Bcl-2 mRNA expressions, and number of Purkinje cells, but lower Bax mRNA expression than the Ovx NMIEx group. All motor functions of MIEx groups were better than the Sham and Ovx groups without MIEx. Motor functions on rotarod task, OFT, and FPT correlated significantly with the mRNAs expression of Bcl-2, Bax, BDNF, synaptophysin, Pgc-1α, and the number of cerebellar Purkinje cells in ovariectomized rats. MIEx improves cerebellar neurotrophic and neuroprotective markers, as well as motor functions of ovariectomized rats.

Anti-obesity effects of instant fermented teas in vitro and in mice with high-fat-diet-induced obesity

Obesity is a chronic metabolic disorder that is associated with higher risks of developing diabetes and cardiovascular disease. Chinese dark tea is a fermented beverage with many biological effects and could be considered for the management of obesity. This study is aimed to assess the possible anti-obesity properties of instant dark tea (IDT) and instant pu-erh tea (PET) in high fat diet (HFD)-fed mice. Male C57BL/6 mice were divided into 5 groups. They received low-fat diet (LFD), HFD, HFD supplemented with drinking IDT infusion (5 mg mL-1), PET infusion (5 mg mL-1) or water for 8 weeks. The results showed IDT exhibited better inhibitory effect than PET on body weight gain and visceral fat weights. IDT also improved the serum high-density lipoprotein cholesterol (HDL-C) level, but decreased the low-density lipoprotein cholesterol (LDL-C) and leptin levels more effectively than PET. Both IDT and PET lowered the levels of aspartate aminotransferase (AST) and alanine aminotransferase (ALT) in the plasma and significantly increased the ratio of albumin to globin (A/G) in the serum compared to the control group. IDT treatment reduced the malondialdehyde (MDA) level in the liver. Histomorphology evidenced that the liver tissue architecture was well preserved by IDT administration. Moreover, IDT regulated the expression of obesity-related genes more effectively than PET. Overall, the present findings have provided the proof of concept that dietary IDT could provide a safer and cost-effective option for people with HFD-induced obesity.

The hypolipidemic effects of peptides prepared from Cicer arietinum in ovariectomized rats and HepG2 cells

BACKGROUND

The lack of estrogen in postmenopausal women is a key risk factor for disorders of lipid metabolism and for obesity. Except in cases where estrogen replacement therapy (ERT) is being used, chickpea peptides (ChPs) may be a potential candidate for treating hyperlipidemia.

RESULTS

In ovariectomized rats model, ChPs were found to decrease body weight, adipose tissue size, total cholesterol (TC), total triglyceride (TG), low-density lipoprotein cholesterol (LDL-C), and the atherogenic index (AI) in serum and liver TC and TG. Serum high-density lipoprotein cholesterol (HDL-C), bile acids in liver and feces, fecal TC and TG were observed to increase significantly (P < 0.05). ChPs play a role in inhibiting the activities of fatty acid synthetase (FAS) and HMG-CoA reductase (HMGR). The expression of peroxisome proliferator-activated receptors (PPAR)γ and sterol regulatory element-binding protein (SREBP)-1c were downregulated and the expression of liver X receptor (LXR) α, estrogen receptor(ER)α and ERβ were upregulated by ChPs. In HepG2 cell experiments, the cellular TC levels decreased and the uptake of NBD-cholesterol increased significantly after treatment with Mw < 1 kDa and Mw < 5 kDa ChPs fractions. Val-Phe-Val-Arg-Asn (VFVRN) could inhibit TC biosynthesis by decreasing the expression of HMGR.

CONCLUSION

We demonstrated that ChPs could effectively regulate lipid metabolism disorders and restrain obesity caused by estrogen deficiency. Val-Phe-Val-Arg-Asn identified from ChPs could reduce the expression of HMGR to inhibit cholesterol biosynthesis. © 2018 Society of Chemical Industry.

Effect of isoflavone-enriched whole soy milk powder supplementation on bone metabolism in ovariectomized mice

BACKGROUND/OBJECTIVE

There is intense interest in soy isoflavone as a hormone replacement therapy for the prevention of postmenopausal osteoporosis. A new kind of isoflavone-enriched whole soy milk powder (I-WSM) containing more isoflavones than conventional whole soy milk powder was recently developed. The aim of this study was to investigate the effects of I-WSM on bone metabolism in ovariectomized mice.

MATERIALS/METHODS

Sixty female ICR mice individually underwent ovariectomy (OVX) or a sham operation, and were randomized into six groups of 10 animals each as follows: Sham, OVX, OVX with 2% I-WSM diet, OVX with 10% I-WSM diet, OVX with 20% I-WSM diet, and OVX with 20% WSM diet. After an 8-week treatment period, bone mineral density (BMD), calcium, alkaline phosphatase (ALP), tartrate-resistant acid phosphatase (TRAP) 5b, osteocalcin (OC), procollagen 1 N-terminal propeptide (P1NP), and osteoprotegenin (OPG) were analyzed.

RESULTS

BMD was significantly lower in the OVX group compared to the Sham group but was significantly higher in OVX + 10% I-WSM and OVX + 20% I-WSM groups compared to the OVX group (P < 0.05). Serum calcium concentration significantly increased in the OVX + 10% and 20% I-WSM groups. Serum ALP levels were significantly lower in the OVX + 10% and 20% I-WSM groups compared to the other experimental groups (P < 0.05). OC was significantly reduced in the OVX group compared to the Sham group (P < 0.05), but a dose-dependent increase was observed in the OVX groups supplemented with I-WSM. P1NP and OPG levels were significantly reduced, while TRAP 5b level was significantly elevated in the OVX group compared with the Sham group, which was not affected by I-WSM (P < 0.05).

CONCLUSIONS

This study suggests that I-WSM supplementation in OVX mice has the effect of preventing BMD reduction and promoting bone formation. Therefore, I-WSM can be used as an effective alternative to postmenopausal osteoporosis prevention.