Applications of Chinese Camellia oleifera and its By-Products: A Review

Camellia oleifera is a woody oil tree species unique to China that has been cultivated and used in China for more than 2,300 years. Most biological research on C. oleifera in recent years has focused on the development of new varieties and breeding. Novel genomic information has been generated for C. oleifera, including a high-quality reference genome at the chromosome level. Camellia seeds are used to process high-quality edible oil; they are also often used in medicine, health foods, and daily chemical products and have shown promise for the treatment and prevention of diseases. C. oleifera by-products, such as camellia seed cake, saponin, and fruit shell are widely used in the daily chemical, dyeing, papermaking, chemical fibre, textile, and pesticide industries. C. oleifera shell can also be used to prepare activated carbon electrodes, which have high electrochemical performance when used as the negative electrode of lithium-ion batteries. C. oleifera is an economically valuable plant with diverse uses, and accelerating the utilization of its by-products will greatly enhance its industrial value.

The hepatoprotective effects of plant-based foods based on the "gut-liver axis": a prospective review

The importance of the "gut-liver axis" in the pathogenesis of liver diseases has been revealed recently; which promotes the process of developing preventive and therapeutic strategies. However, considering that there are still many challenges in the medical treatment of liver diseases, potential preventive dietary intervention may be a good alternative choice. Plant-based foods have received much attention due to their reported health-promoting effects in targeting multiple pathways involved in the pathogenesis of liver diseases as well as the relative safety for general use. Based on the PubMed and Web of Science databases, this review emphatically summarizes the plant-based foods and their chemical constituents with reported effects to impact the LPS/TLR4 signaling pathway of gut-liver axis of various liver diseases, reflecting their health benefits in preventing/alleviating liver diseases. Moreover, some plant-based foods with potential gut-liver effects are specifically analyzed from the reported studies and conclusions. This review intends to provide readers an overview of the current progress in the field of this research topic. We expect to see more hepatoprotective measures for alleviating the current prevalence of liver diseases.

Beneficial Effect of Thymelaea hirsuta on Pancreatic Islet Degeneration, Renal Fibrosis, and Liver Damages as Demonstrated in Streptozotocin-Induced Diabetic Rat

OBJECTIVE

In Morocco, Thymelaea hirsuta (T. hirsuta) (Thymelaeacea) is a medicinal plant widely used to treat and prevent diabetes. The present study aimed to evaluate the medium-term antidiabetic effect of aqueous extract (AqTh) and ethyl acetate fraction (EaTh) of Th and to investigate their putative protective effect on pancreatic islet degeneration, diabetic nephropathy, and liver damages in streptozotocin (STZ)-diabetic rats.

METHODS

Experimental diabetes in rats was induced by a single intraperitoneal injection of 50 mg/kg of STZ. During the treatment period (4 weeks), 200 mg/kg AqTh and 50 mg/kg EaTh were orally administrated daily to STZ-diabetic rats. A group of parameters including fasting blood glucose, biochemical parameters, and intestinal α-glucosidase inhibition were studied. Furthermore, histological study of the pancreas, kidney, liver, and aorta was also realized.

RESULTS

At the end of the treatment, both AqTh and EaTh had normalized fasting blood glucose to 1.08 and 1.25 g/l, respectively. AqTh has also reduced urinary creatinine and HbAc1. The EaTh showed inhibitory activity against intestinal α-glucosidase, whereas AqTh did not have this inhibitory effect. Furthermore, pancreas hematoxylin and eosin staining showed that AqTh or EaTh prevents pancreatic islet cell degeneration. As the same kidney, Masson's trichrome staining has shown a significant prevention of renal fibrosis in AqTh- or EaTh-treated diabetic rats. On the other hand, liver hematoxylin and eosin staining showed that AqTh and EaTh prevent liver damage.

CONCLUSION

We conclude that medium-term administration of AqTh and EaTh exerts significant antihyperglycemic effect in STZ-diabetic rats possibly through intestinal α-glucosidase inhibition and protection against pancreatic islet cell damage. Moreover, AqTh and EaTh treatment prevent nephropathy and liver complications in STZ-diabetic rats.

Improvement in Menopause-Associated Hepatic Lipid Metabolic Disorders by Herbal Formula HPC03 on Ovariectomized Rats

Postmenopausal women have an increased risk of developing nonalcoholic fatty liver disease (NAFLD). We formulated a combination of three herb mixtures (HPC03) and observed lipid-lowering efficacy. HepG2 cells were treated with oleic acid to induce an NAFLD model (in vitro). Also, we investigated potential of HPC03 in an ovariectomize- (OVX-) induced NAFLD model (in vivo). We separated the mice into six groups, as follows: SHAM, OVX, OVX + β-estradiol, and OVX + HPC03 (50, 100, and 200 mg/kg). Rats were administered with/without HPC03 for 12 weeks. HPC03 dose dependently inhibited the lipid accumulation involved in lipogenesis in HepG2 cells. The body weight, fat mass, and weights of the liver were decreased in the OVX group than that in the other groups. HPC03 had decreased adiposity that was induced by OVX. HPC03 treatment reduced liver lipid deposition and prevented the increase in serum and liver triglyceride export when there was a deficiency in estradiol. HPC03 improves OVX-induced fatty liver and lipid metabolism. These findings suggest that HPC03 from postmenopausal women has a protective effect during NAFLD conditions.

Crude extract of Camellia oleifera pomace ameliorates the progression of non-alcoholic fatty liver disease via decreasing fat accumulation, insulin resistance and inflammation

Consumption of a high-fat diet increases fat accumulation and may further lead to inflammation and hepatic injuries. The aim of the study was to investigate the effects of Camellia oleifera seed extract (CSE) on non-alcoholic fatty liver disease (NAFLD). After a 16-week NAFLD-inducing period, rats were assigned to experimental groups fed an NAFLD diet with or without CSE. At the end of the study, we found that consuming CSE decreased the abdominal fat weight and hepatic fat accumulation and modulated circulating adipokine levels. We also found that CSE groups had lower hepatic cytochrome P450 2E1 and transforming growth factor (TGF)-β protein expressions. In addition, we found that CSE consumption may have affected the gut microbiota and reduced toll-like receptor (TLR)-4, myeloid differentiation primary response gene 88, toll/IL-1 receptor domain-containing adaptor-inducing interferon-β (TRIF) expression and proinflammatory cytokine concentrations in the liver. Our results suggest that CSE may alleviate the progression of NAFLD in rats with diet-induced steatosis through reducing fat accumulation and improving lipid metabolism and hepatic inflammation.

Effect of β-sitosterol self-microemulsion and β-sitosterol ester with linoleic acid on lipid-lowering in hyperlipidemic mice

Background

The hypolipidemic effect of phytosterols has been wildely recognized, but its application is limited due to its insolubility in water and low solubility in oil. In this study, β-sitosterol ester with linoleic acids and β-sitosterol self-microemulsions were prepared and their hypolipidemic effects on hyperlipidemia mice were studied.

Methods

Firstly, the mice were randomly divided into normal group and model group,they were fed with basic diet and high-fat diet for 70 days respectively. After high-fat model mice was successfully established, the model group was further divided into eight groups: HFD (high-fat diet feeding), SELA-TSO(8 ml/kg, SELA:700 mg/kg), TSO (8 ml/kg), SSSM (8 ml/kg,SS:700 mg/kg), NLSM (8 ml/kg), SSHT-TSO (8 ml/kg, SS: 700 mg/kg) and SS-TSO (8 ml/kg, SS: 700 mg/kg) groups, and treated with β-sitosterol ester with linoleic acid, β-sitosterol self-microemulsion, commercial β-sitosterol health tablets and β-sitosterol powder for 35 days, respectively, and blank control groups were established. At the end of the treatment period, the blood lipid level, tissues, cholesterol and lipids in feces of mice in each group were investigated. Statistical and analytical data with SPSS 17.0 Software,statistical significance was set at p* < 0.05 and p** < 0.01 levels .

Results

The order of lowering blood lipid effect is listed as: SSSM> SELA-TSO > SSHT-TSO > SS-TSO, which shows that β-sitosterolself-microemulsion have the highest treatment effect among the experimental groups.

Conclusions

In this study, a new formulation of β-sitosterol was developed, and its hypolipidemic effect was investigated. The results showed that β-sitosterol self-microemulsion has a good blood lipid lowering effect.