Eucommia ulmoides Oliv. (EU), also known as Du-Zhong, is a medicinal herb commonly used in Asia to treat hypertension and diabetes. Despite evidence of the protective effects of EU against diabetes, its precise effects and mechanisms of action against advanced glycation end-products (AGEs) are unclear. In this study, we evaluated the effects of EU on AGEs-induced renal disease and explored the possible underlying mechanisms using streptozotocin (STZ)-induced diabetic mice. STZ-induced diabetic mice received EU extract (200 mg/kg) orally for 6 weeks. EU treatment did not change blood glucose and glycated hemoglobin (HbA1c) levels in diabetic mice. However, the EU-treated group showed a significant increase in the protein expression and activity of glyoxalase 1 (Glo1), which detoxifies the AGE precursor, methylglyoxal (MGO). EU significantly upregulated nuclear factor erythroid 2-related factor 2 (Nrf2) expression but downregulated that of receptor for AGE (RAGE). Furthermore, histological and immunohistochemical analyses of kidney tissue showed that EU reduced periodic acid–Schiff (PAS)-positive staining, AGEs, and MGO accumulation in diabetic mice. Based on these findings, we concluded that EU ameliorated the renal damage in diabetic mice by inhibiting AGEs formation and RAGE expression and reducing oxidative stress, through the Glo1 and Nrf2 pathways.
Although the prevalence of metabolic disorders has progressively increased over the past few decades, metabolic disorders can only be effectively treated with calorie restriction and improved physical activity. Recent research has focused on altering the gut microbiome using prebiotics, probiotics, and postbiotics because various metabolic syndromes are caused by gut microbial dysbiosis. Postbiotics, substances produced or released by microorganism metabolic activities, play an important role in maintaining and restoring host health. Because postbiotics have a small amount of literature on their consumption, there is a need for more experiments on short- and long-term intake. This review discusses current postbiotic research, categories of postbiotics, positive roles in metabolic syndromes, and potential therapeutic applications. It covers postbiotic pleiotropic benefits, such as anti-obesity, anti-diabetic, and anti-hypertensive qualities, that could aid in the management of metabolic disorders. Postbiotics are promising tools for developing health benefits and therapeutic goals owing to their clinical, technical, and economic properties. Postbiotic use is attractive for altering the microbiota; however, further studies are needed to determine efficacy and safety.
Ultraviolet (UV) light is a physical carcinogen, and UV irradiation from sunlight has negative effects on human skin. UVB-induced inflammation is linked to excessive induction of various inflammatory cytokines/chemokines in many types of cells, including keratinocytes. The purpose of this study was to investigate the anti-inflammatory effect of water extract of Zingiber officinale , gingerol, and shogaol on UVB-induced skin damage in the human keratinocyte cell line HaCaT and C57BL/6 mice. To test for an effective compound to protect against inflammation in UV-damaged skin, we prepared a water extract of ginger rhizomes and examined the effects of Z. officinale , gingerol, and shogaol on cell viability and cytokine/chemokine production in UV-irradiated HaCaT cells. We also investigated the in vivo relevance of these findings in C57BL/6 mice using hematoxylin and eosin staining and cytokine measurements. A water extract of Z. officinale , gingerol, and shogaol inhibited production of cytokines in UVB-irradiated HaCaT cells effectively. Treatment with Z. officinale attenuated UVB-induced hyperplasia, infiltration of leukocytes, and dilation of blood vessels in the dermis of mice. Z. officinale , gingerol, and shogaol show potential as anti-inflammatory agents to protect skin against UVB irradiation damage.
The aim of this study was to improve the anti-inflammatory activities of apigenin through co-treatment with resveratrol as a bioenhancer of apigenin. RAW 264.7 cells pretreated with hepatic metabolites formed by the co-metabolism of apigenin and resveratrol (ARMs) in HepG2 cells were stimulated with lipopolysaccharide (LPS). ARMs prominently inhibited (p < 0.05) the production of nitric oxide (NO), prostaglandin E2 (PGE2), interleukin (IL)-1β, IL-6 and TNF-α. Otherwise no such activity was observed by hepatic metabolites of apigenin alone (AMs). ARMs also effectively suppressed protein expressions of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2). Co-administration of apigenin (50 mg/kg) and resveratrol (25 mg/kg) also showed a significant reduction of carrageenan-induced paw edema in mice (61.20% to 23.81%). Co-administration of apigenin and resveratrol led to a 2.39 fold increase in plasma apigenin levels compared to administration of apigenin alone, suggesting that co-administration of resveratrol could increase bioavailability of apigenin. When the action of resveratrol on the main apigenin metabolizing enzymes, UDP-glucuronosyltransferases (UGTs), was investigated, resveratrol mainly inhibited the formation of apigenin glucuronides by UGT1A9 in a non-competitive manner with a Ki value of 7.782 μM. These results suggested that resveratrol helps apigenin to bypass hepatic metabolism and maintain apigenin’s anti-inflammatory activities in the body.
Curcuma longa L. (turmeric) has been used as a functional food material, but other parts of it such as leaves are wasted as a byproduct. This work concentrated on developing turmeric leaves as a functional food material by establishing its optimal extraction condition. Response surface methodology was applied to optimize turmeric leaf extraction conditions. Turmeric leaves were pulled out with water and ethanol (10, 30, and 50%). Then, total phenolic compound content, total flavonoid content, and radical-scavenging activity of each extract were quantified to confirm the optimal extracting solvent. According to the results, water was the most efficient solvent to extract antioxidant contents such as total phenolic compounds (3.65 ± 0.02 mg GAE/g) and flavonoids (4.99 ± 0.17 mg QCE/g) content. Radical-scavenging activity was also higher in water extract compared with others such as DPPH (51.10 ± 2.29%), H2O2 (25.39 ± 2.69%), and ABTS (91.08 ± 0.15%). Central composite design was applied to confirm the effect of independent variables such as temperature (X1) and time (X2) to the yield (Y1). After conducting experiments, the extraction condition was established as 150 min with 1 : 25 ratio at 85°C with a 15.58% yield. Proximate compositions of the extract were determined to suggest background data for further research. In conclusion, this study confirmed the antioxidant property of turmeric leaves and developed the optimal extraction condition of the leaves to promote its application in food industry as a new food source.