The structures of two polysaccharides from Angelica sinensis and their effects on hepatic insulin resistance through blocking RAGE

Guava polysaccharides attenuate high fat and STZ-induced hyperglycemia by regulating gut microbiota and arachidonic acid metabolism

This study investigated the hypoglycemic mechanism of guava polysaccharides (GP) through the gut microbiota (GM) and related metabolites. Our findings demonstrated that GP significantly mitigated high-fat diet- and streptozotocin-induced hyperglycemia, insulin resistance, hyperlipidemia, elevated alanine aminotransferase, high hepatic inflammation levels, and prevented pancreatic atrophy and hepatomegaly. Interestingly, the benefits of GP were attributed to alterations in the GM. GP decreased the ratio of Firmicutes to Bacteroidetes, significantly inhibiting deleterious bacteria, including Uncultured_f_Desulfovibrionaceae, Bilophila, and Desulfovibrio, while promoting the proliferation of probiotic Bifidobacterium and Bacteroides. In addition, GP promoted the generation of short-chain fatty acids. Notably, the arachidonic acid (AA) metabolism pathway was enriched in liver metabolites. GP significantly elevated hepatic AA and 15-hydroxyeicosatetraenoic acid, while reducing prostaglandin E2 and 5- and 12-hydroxyeicosatetraenoic acid. This modulation is accompanied by the downregulation of hepatic cyclooxygenase-1, 12-lipoxygenase, P38, and c-Jun N-terminal kinase mRNA expression, and the upregulation of cytochrome P4502J5 and insulin receptor substrate 1/2 mRNA expression. However, GP antibiotic treatment did not induce significant alterations in FBG and AA levels or gene expression. Overall, our findings suggest that the hypoglycemic effect of GP may be intricately linked to alterations in AA metabolism, which depends on the GM.

A novel glycoglycerolipid from Holotrichia diomphalia Bates: Structure characteristics and protective effect against DNA damage

A lipidated polysaccharide, HDPS-2II, was isolated from the dried larva of Holotrichia diomphalia, which is used in traditional Chinese medicine. The molecular weight of HDPS-2II was 5.9 kDa, which contained a polysaccharide backbone of →4)-β-Manp-(1 → 4,6)-β-Manp-(1 → [6)-α-Glcp-(1]n → 6)-α-Glcp→ with the side chain α-Glcp-(6 → 1)-α-Glcp-(6 → linked to the C-4 of β-1,4,6-Manp and four types of lipid chains including 4-(4-methyl-2-(methylamino)pentanamido)pentanoic acid, 5-(3-(tert-butyl)phenoxy)hexan-2-ol, N-(3-methyl-5-oxopentan-2-yl)palmitamide, and N-(5-amino-3-methyl-5-oxopentan-2-yl)stearamide. The lipid chains were linked to C-1 of terminal α-1,6-Glcp in carbohydrate chain through diacyl-glycerol. HDPS-2II exhibited DNA protective effects and antioxidative activity on H2O2- or adriamycin (ADM)-induced Chinese hamster lung cells. Furthermore, HDPS-2II significantly ameliorated chromosome aberrations and the accumulation of reactive oxygen species (ROS), reduced γ-H2AX signaling and the expressions of NADPH oxidase (NOX)2, NOX4, P22phox, and P47phox in ADM-induced cardiomyocytes. Mechanistically, HDPS-2II suppressed ADM-induced up-regulation of NOX2 and NOX4 in cardiomyocytes, but not in NOX2 or NOX4 knocked-down cardiomyocytes, indicating that HDPS-2II could relieve intracellular DNA damage by regulating NOX2/NOX4 signaling. These findings demonstrate that HDPS-2II is a new potential DNA protective agent.

The angelica Polysaccharide: a review of phytochemistry, pharmacology and beneficial effects on systemic diseases

Angelica sinensis is a perennial herb widely distributed around the world, and angelica polysaccharide (APS) is a polysaccharide extracted from Angelica sinensis. APS is one of the main active components of Angelica sinensis. A large number of studies have shown that APS has hematopoietic, promoting blood circulation, radiation resistance, lowering blood glucose, enhancing the body immunity and other pharmacological effects in a variety of diseases. However, different extraction methods and extraction sites greatly affect the efficacy of APS. In recent years, with the emerging of new technologies, there are more and more studies on the combined application and structural modification of APS. In order to promote the comprehensive development and in-depth application of APS, this narrative review systematically summarizes the effects of different drying methods and extraction sites on the biological activity of APS, and the application of APS in the treatment of diseases, hoping to provide a scientific basis for the experimental study and clinical application of APS.

Structural characterization of the polysaccharide from the black crystal region of Inonotus obliquus and its effect on AsPC-1 and SW1990 pancreatic cancer cell apoptosis

In this study, one water soluble polysaccharide (IOP1-1) with a weight average molecular weight of 6886 Da was obtained from the black crystal region of Inonotus obliquus by hot water extraction, DEAE-52 cellulose extraction and Sephadex-100 column chromatography purification. Structural analysis indicated that IOP1-1 was a glucan with a main chain composed of α-Glcp-(1 → 4)-α-Glcp-(1 → 4)-β-Glcp-(1 → 4)-β-Glcp-(1 → 4)-α-Glcp-(1 → 6)-β-Glcp-(1 → 4)-α-Glcp-(1 → 3)-β-Glcp-(1→. The CCK-8 assay results showed that IOP1-1 inhibited AsPC-1 and SW1990 pancreatic cancer cell proliferation in a concentration-dependent manner. Flow cytometric analysis revealed that IOP1-1 induced cell cycle arrest in AsPC-1 and SW1990 cells. Hoechst 33342 staining and Annexin V-FITC/PI double staining analysis showed that IOP1-1 could induce apoptosis in AsPC-1 and SW1990 cells. Furthermore, western blot analysis confirmed that IOP1-1 could induce apoptosis in AsPC-1 and SW1990 pancreatic cancer cells through three pathways: the mitochondrial pathway, the death receptor pathway, and endoplasmic reticulum stress. According to these research data, IOP1-1 may be utilized as an adjuvant treatment to anticancer medications, opening up new application prospects and opportunities.

Structural characterization and ferroptosis-related immunomodulatory of a novel exopolysaccharide isolated from marine fungus Aspergillus medius

Marine fungal exopolysaccharides play a crucial role in immunoregulation. In this investigation, a novel polysaccharide was extracted from the culture medium of the marine fungus Aspergillus medius SCAU-236. Compositional analysis revealed a structure composed of glucose units with (1,4)-α-D-Glcp, (1,3,4)-β-D-Glcp, and (1,4,6)-α-D-Glcp, along with side chains of 1-α-D-Glcp linked to carbon 6 of (1,4,6)-α-D-Glcp and carbon 3 of (1,3,4)-β-D-Glcp. Functional evaluations on RAW264.7 macrophage cells demonstrated Aspergillus medius polysaccharide (ASMP)'s effects on cell proliferation, nitric oxide levels, and the secretion of TNF-α, IL-6, and IL-1β cytokines. Additionally, metabolomics indicated ASMP's potential to modulate macrophage immune function by impacting key regulatory molecules, including COX-2, iNOS, Nrf2, SLC7A11, GPX4, and ACSL4. The Nrf2/SLC7A11/GPX4 axis and ACSL4 were suggested to be involved in ASMP-induced ferroptosis, leading to increased reactive oxygen species (ROS) levels and lipid peroxidation. These findings propose a unique mechanism by which ASMP exerts immunomodulatory effects through ferroptosis induction, contributing to the understanding of marine-derived compounds in immunomodulation research.

Recent advances in medicinal and edible homologous plant polysaccharides: Preparation, structure and prevention and treatment of diabetes

Medicinal and edible homologs (MEHs) can be used in medicine and food. The National Health Commission announced that a total of 103 kinds of medicinal and edible homologous plants (MEHPs) would be available by were available in 2023. Diabetes mellitus (DM) has become the third most common chronic metabolic disease that seriously threatens human health worldwide. Polysaccharides, the main component isolated from MEHPs, have significant antidiabetic effects with few side effects. Based on a literature search, this paper summarizes the preparation methods, structural characterization, and antidiabetic functions and mechanisms of MEHPs polysaccharides (MEHPPs). Specifically, MEHPPs mainly regulate PI3K/Akt, AMPK, cAMP/PKA, Nrf2/Keap1, NF-κB, MAPK and other signaling pathways to promote insulin secretion and release, improve glycolipid metabolism, inhibit the inflammatory response, decrease oxidative stress and regulate intestinal flora. Among them, 16 kinds of MEHPPs were found to have obvious anti-diabetic effects. This article reviews the prevention and treatment of diabetes and its complications by MEHPPs and provides a basis for the development of safe and effective MEHPP-derived health products and new drugs to prevent and treat diabetes.

Advances in polysaccharides of natural source of anti-diabetes effect and mechanism

PURPOSE

Diabetes is a chronic disease in metabolic disorder, and the pathology is characterized by insulin resistance and insulin secretion disorder in blood. In current, many studies have revealed that polysaccharides extracted from natural sources with significant anti-diabetic effects. Natural polysaccharides can ameliorate diabetes through different action mechanisms. All these polysaccharides are expected to have an important role in the clinic.

METHODS

Existing polysaccharides for the treatment of diabetes are reviewed, and the mechanism of polysaccharides in the treatment of diabetes and its structural characteristics are described in detail.

RESULTS

This article introduced the natural polysaccharide through different mechanisms of action in the treatment of diabetes, including oxidative stress, apoptosis, inflammatory response and regulation of intestinal bacteria. Natural polysaccharides can treat of diabetes by regulating signaling pathways is also a research hotspot. In addition, the structural characteristics of polysaccharides were explored. There are some structure-activity relationships between natural polysaccharides and the treatment of diabetes.

Antifungal mechanism of Angelica sinensis essential oil against Penicillium roqueforti and its application in extending the shelf life of bread

There are a variety of reports on the application of Angelica sinensis essential oil (ASEO) in the biomedical field. However, the antifungal mechanism of ASEO has not been reported. In this study, the antifungal mechanism of ASEO against Penicillium roqueforti was investigated by proteomics and genomics. ASEO can increase the permeability of P. roqueforti cell membrane and decrease the content of lipid and trehalose. With the increase of glycerol content, the HOG signaling pathway can be upregulated. Consistent with the above phenotypic changes, proteomics confirmed that ASEO treatment inhibited the steroid synthesis pathway of P. roqueforti. The significant down-regulation of ERG4, ERG6, ERG25, SMT1, and FDFT1 gene expression confirmed this conclusion. Cluster+activates the MAPK and UPP signaling pathways and ultimately leads to cell apoptosis. The bread shelf life experiment showed that ASEO could extend the shelf life of bread up to day 7. This study provides new evidence for the antifungal activity of ASEO against P. roqueforti and will promote the use of ASEO in the preservation of food and agricultural products.

Polysaccharides from Chinese herbal medicine: a review on the hepatoprotective and molecular mechanism

Polysaccharides, predominantly extracted from traditional Chinese medicinal herbs such as Lycium barbarum, Angelica sinensis, Astragalus membranaceus, Dendrobium officinale, Ganoderma lucidum, and Poria cocos, represent principal bioactive constituents extensively utilized in Chinese medicine. These compounds have demonstrated significant anti-inflammatory capabilities, especially anti-liver injury activities, while exhibiting minimal adverse effects. This review summarized recent studies to elucidate the hepatoprotective efficacy and underlying molecular mechanisms of these herbal polysaccharides. It underscored the role of these polysaccharides in regulating hepatic function, enhancing immunological responses, and improving antioxidant capacities, thus contributing to the attenuation of hepatocyte apoptosis and liver protection. Analyses of molecular pathways in these studies revealed the intricate and indispensable functions of traditional Chinese herbal polysaccharides in liver injury management. Therefore, this review provides a thorough examination of the hepatoprotective attributes and molecular mechanisms of these medicinal polysaccharides, thereby offering valuable insights for the advancement of polysaccharide-based therapeutic research and their potential clinical applications in liver disease treatment.

Polysaccharide from walnut green husk alleviates liver inflammation and gluconeogenesis dysfunction by altering gut microbiota in ochratoxin A-induced mice

Walnut green husk polysaccharides (WGP) are isolated from the walnut green husk with a mean molecular weight of 12.77 kDa. The structural characterization revealed by methylation and NMR analysis indicated that WGP might consist of →4-α-D-Galp-(1→, α-D-Galp (1→, and →2)-α-L-Rhap-(1→. Previous studies have been demonstrated that WGP effectively prevented liver injury and modulated gut microbiota in high fructose-treated mice and high fat diet-treated rats. In this study, we found for the first time that WGP presenting outstanding protective effects on liver inflammation and gluconeogenesis dysfunction induced by ochratoxin A (OTA) in mice. Firstly, WGP decreased oxidative stress, down-regulated the expression of inflammatory factors and inhibited the TLR4/p65/IκBα pathway in the liver. Then, WGP reversed OTA-induced lower phosphoenolpyruvate carboxyl kinase (PEPCK), and glucose 6-phosphatase (G6PC) activities in the liver. Furthermore, WGP increased the diversity of gut microbiota and the abundance of beneficial bacteria, especially Lactobacillus and Akkermansia. Importantly, the results of fecal microbiota transplantation (FMT) experiment further confirmed that gut microbiota involved in the protective effects of WGP on liver damage induced by OTA. Our results indicated that the protective effect of WGP on liver inflammation and gluconeogenesis dysfunction caused by OTA may be due to the regulation of gut microbiota.

A polysaccharide NAP-3 from Naematelia aurantialba: Structural characterization and adjunctive hypoglycemic activity

A novel polysaccharide (NAP-3) was isolated and purified from Naematelia aurantialba after water extraction. The structure of NAP-3, which was determined by FT-IR, HPLC, GC-MS, and NMR, indicated that NAP-3 was a homogeneous polysaccharide with the molecular weight of 428 kDa, mainly consisted of β-1, 3-D-Manp, β-1, 2, 3-D-Manp, β-D-Xylp, β-1, 4-D-Glcp, β-1, 4-D-Rhap in a molar ratio of 6.49: 1.11: 2.4: 0.13: 0.83. In vitro α-glucosidase and α-amylase inhibitory assay showed that NAP-3 had a low IC₅₀ value, which exhibited similar enzyme inhibitory activity as acarbose. NAP-3 was evaluated as an adjuvant with metformin for antidiabetic therapy in HFD/STZ-induced diabetic mice and insulin resistance HepG2 cells. The combination of NAP-3 and metformin in diabetic mice exhibited significant hypoglycemic activity, reducing body weight, serum insulin levels, glucose tolerance, insulin tolerance, and increasing antioxidant levels compared to metformin alone. The combination of NAP-3 and metformin improved oxidative stress by increasing ROS clearance, thereby enhancing glucose uptake in HepG2 cells. This study provided new data for the study of Naematelia aurantialba polysaccharides and offers a new adjuvant therapy for the treatment of diabetes.

Carbon Quantum Dots Derived from Herbal Medicine as Therapeutic Nanoagents for Rheumatoid Arthritis with Ultrahigh Lubrication and Anti-inflammation

As a typical chronic inflammatory joint disease with swelling and pain syndromes, rheumatoid arthritis (RA) is closely related to articular lubrication deficiency and excessive proinflammatory cytokines in its progression and pathogenesis. Herein, inspired by the dual effects of joint lubrication improvement and anti-inflammation to treat RA, two novel potential therapeutic nanoagents have been developed rationally by employing herbal medicine-derived carbon quantum dots (CQDs), i.e., safflower (Carthamus tinctorius L.) CQDs and Angelica sinensis CQDs, yielding ultrahigh lubrication and anti-inflammation bioefficacy. In vitro experimental results show that the two nanoagents display excellent friction reduction due to their good water solubility and spherical structure. Using RA rat models, it is indicated that the nanoagents significantly relieved swelling symptoms and inhibited the expression of related inflammatory cytokines, including IL-1, IL-6, and TNF-α, indicating their extraordinary anti-inflammation bioefficacy. Thus, combining the lubricating and anti-inflammation bioefficacy of CQDs derived from herbal medicine is an attractive strategy to develop new nanoagents for RA treatment.

Structural Characterization and Anti-inflammatory Activities of Anticomplementary Polysaccharides from Rhododendron principis

Rhododendron principis leaves have been used as "Dama", a Traditional Tibetan Medicine for treating inflammatory diseases. R. principis crude polysaccharides with anticomplementary activity demonstrated promising anti-inflammatory effects on acute lung injury induced by lipopolysaccharide. R. principis crude polysaccharides significantly decreased the levels of TNF-α and interleukin-6 in both serum and blood and bronchoalveolar lavage fluid in lipopolysaccharide-induced acute lung injury mice by intragastric administration (100 mg/kg). A heteropolysaccharide, ZNDHP, was obtained from R. principis crude polysaccharides with successive anticomplementary activity-guided separation. ZNDHP was characterized as a branched neutral polysaccharide with a backbone composed of → 2)-β-Glcp-(1→, → 2,6)-α-Glcp-(1→, → 6,3)-β-Galp-(1→, → 2,6)-α-Galp-(1→, → 6,2)-β-Glcp-(1→, → 4)-α-Glcp-(1→, → 5)-β-Araf-(1→, → 3,5)-α-Araf-(1→, and → 4,6)-β-Manp-(1→, and the backbone structure was further confirmed by partial acid hydrolysis. In addition to anticomplementary and antioxidant activities, ZNDHP exhibited potent anti-inflammatory activity by significantly inhibiting the secretion of nitric oxide, TNF-α, interleukin-6, and interleukin-1β of lipopolysaccharide-treated RAW 264.7 cells. However, all of these activities decreased greatly after partially hydrolyzing, indicating the importance of the multibranched structure for its bioactivity. Therefore, ZNDHP might be an important component of R. principis for treating inflammation.

Isolation, Structural Characteristics Analysis of a Vigna unguiculata Polysaccharide VUP80-3 and Its Protective Effect on GES-1 Cells In Vitro

Cowpea (Vigna unguiculata) is one of the main edible legume vegetables in China, and it can improve spleen and stomach function. A polysaccharide component (VUP80-3) has been isolated from V. unguiculata in this study. The average molecular weight of VUP80-3 is 6.43 × 10⁴ Da, and the main monosaccharide group is glucose. The mass ratio of monosaccharide groups in the polysaccharide was glucose:galactose:arabinose:rhamnose:xylose:mannose:fucose = 152.36:24.50:16.53:8.13:1.26:0.97:0.82. NMR analysis showed that VUP80-3 has →4)-α-D-Galp (1→ and →4)-α-D-Glcp(1→ main chain and →3,4)-β-D-Glcp(1→, →4,6)-α-D-Glcp(1→ branch chains, and the terminal sugar is α-D-Glcp(1→. Biological activity test results showed that VUP80-3 at 1000 μg·mL^-1 significantly increased the activity of ethanol injured GES-1 cells (p < 0.01) and significantly reduced reactive oxygen species (ROS) in ethanol injured GES-1 cells and inflammatory factors (IL-8, IL-1β and TNF-α,) in GES-1 cells. This compound also reduced the apoptosis rate (p < 0.05), thereby significantly reducing the oxidative damage caused by ethanol in GES-1 cells. Therefore, VUP80-3 is a potential drug to protect the gastric mucosa from damage.

Angelica sinensis polysaccharide extends lifespan and ameliorates aging-related diseases via insulin and TOR signaling pathways, and antioxidant ability in Drosophila

Angelica sinensis polysaccharide (ASP) is one of the principal active components of Angelica sinensis (AS) that is widely used in natural medicine and has various pharmacological activities, including antioxidant, anti-inflammatory, and enhancing immunity. However, its pharmacological role of anti-aging needs to be clarified. Here, we detected the beneficial effect and mechanism of ASP on healthy aging and aging-related diseases using the Drosophila melanogaster model. The results showed that oral administration of ASP remarkably extended lifespan, increased reproduction, improved climbing ability, and increased resistance to starvation and oxidative stress in aged flies, mainly via inhibiting insulin signaling (IIS) and TOR signaling and boosting antioxidant ability. Further, ASP supplementation protected against aging-induced intestinal homeostasis imbalance via inhibiting intestinal stem cells (ISCs) hyperproliferation and oxidative damage, improved sleep disorders via rescuing sleep rhythm in aged flies, and had a neuroprotective effect on Aβ42 transgenic flies. Taken together, our findings shed light on the possibility that ASP could increase lifespan, improve healthy aging, and ultimately reduce the incidence of age-related illnesses. It holds promise as a candidate for anti-aging intervention and treatment for aging-associated disorders.

Structure of a Pueraria root polysaccharide and its immunoregulatory activity on T and B lymphocytes, macrophages, and immunosuppressive mice

In this experiment, the polysaccharide was extracted from Pueraria lobata (Willd.) Ohwi, and its structural characteristics and bioactivity were investigated. The results showed that Pueraria lobata polysaccharide (PLP) was composed of fucose, arabinose, galactose, glucose, xylose, mannose in a molar proportion of 0.09:1.25:2.19:95.74:0.43:0.30 with a number molar masses (Mn) weight of 14.463 kDa. Besides, FT-IR, Methylation, and NMR analysis revealed that PLP were mainly composed of the main chain →4)-α-Glcp (1→ and →4,6)-α-Glcp (1→, and the branched chain α-Glcp (1→. In vitro experiment, the results showed that PLP could stimulate the expression of surface molecules on RAW264.7 and (T and B) lymphocytes proliferation, simultaneously to stimulate their cytokines secretion. In vivo experiment, the immune organ index, cytokine content, and T lymphocyte subtype in cyclophosphamide-induced immunosuppressed mice could be improved by PLP. These data proved that PLP could be used as a useful immunomodulator to enhance the immune activity of RAW264.7, T, and B cells and improve the immune function of cyclophosphamide-treated mice.

Medicine-food herb: Angelica sinensis, a potential therapeutic hope for Alzheimer's disease and related complications

Alzheimer's disease (AD) is a progressive neurodegenerative disease, which has brought a huge burden to the world. The current therapeutic approach of one-molecule-one-target strategy fails to address the issues of AD because of multiple pathological features of AD. Traditionally, the herb of Angelica sinensis (AS) comes from the root of an umbrella plant Angelica sinensis (Oliv.) Diels. As a typical medicine-food herb, studies have shown that AS can alleviate AD and AD-complications by multiple targets through the various foundations of pharmaceutical material and dietary supply basis. Therefore, this review summarizes the pharmacological effects of AS for the treatment of AD and AD-complications for the first time. AS contains many effective components, such as ligustilide, z-ligustilide, n-butylidenephthalide, α-pinene, p-cymene, myrcene, ferulic acid, vanillic acid and coniferyl ferulate. It is found that AS, AS-active compounds and AS-compound recipes mainly treat AD through neuroprotective, anti-inflammation, and anti-oxidant effects, improving mitochondrial dysfunction, anti-neuronal apoptosis, regulating autophagy, regulating intestinal flora and enhancing the central cholinergic system, which shows the multi-component and multi-target effect of AS. The role of dietary supplement components in AS for AD intervention is summarized, including vitamin B₁₂, folic acid, arginine, and oleic acid, which can improve the symptoms of AD. Besides, this review focuses on the safety and toxicity evaluation of AS, which provides a basis for its application. This review will provide further support for the research on AD and the application of medicine-food herb AS in a healthy lifestyle in the future.

Isolation, purification and characterization of Pueraria lobata polysaccharide and its effects on intestinal function in cyclophosphamide-treated mice

This study investigated the structure of acidic Pueraria lobata polysaccharide (a-PLP) and its bioactive effects on intestinal function in cyclophosphamide (CY)-treated mice. The structure of a-PLP was preliminarily analyzed, and the results showed that it is composed of fucose, arabinose, rhamnose, galactose, glucose, xylose, mannose, galacturonic acid, and glucuronic acid in a molar proportion of 2.54:16.52: 6.14: 16.60: 4.05: 4.75: 0.48: 47.44: 1.47 with a weight average molecular weight of 22.675 kDa. In addition, the methylation analysis suggested that 4-Gal(p)-UA may be the main backbone of a-PLP. Furthermore, a-PLP (1.2 g/kg, 0.8 g/kg, and 0.4 g/kg) was administered orally for the treatment of CY-treated mice. The results showed that a-PLP could remarkably relieved weight loss and intestinal villous atrophy in CY-treated mice. Meanwhile, the secretion levels of sIgA, β-defensin, cytokines, Mucin-2, and tight junction proteins increased significantly. Moreover, the ratio of T (CD4⁺ and CD8⁺) cells in the Peyer's patches and mesenteric lymph nodes also increased remarkably, along with the number of goblet cells. Furthermore, a-PLP decreased the levels of diamino oxidase and malondialdehyde, but up-regulated the activity of superoxide dismutase. In summary, a-PLP exhibited great benefits by attenuating CY side effects, opening a potential avenue to effectively treat cancer and reduce the suffering of chemotherapy patients.

Selenium-containing polysaccharides isolated from Rosa laevigata Michx fruits exhibit excellent anti-oxidant and neuroprotective activity in vitro

Selenium-containing polysaccharides have potential as an organic selenium dietary supplement, owing to their low toxicity, few side effects, and easy absorption attributes. In this study, we isolated two novel homogeneous selenium-containing polysaccharides from Rosa laevigata Michx fruits (Se-RLFPs). Results from primary structural analysis revealed that Se-RLFPs were α - pyranose, and were both composed of rhamnose, xylose, glucose with an average molecular weight of 24 and 16 KDa, respectively. Selenium contents in Se-RLFP-I and Se-RLFP-II were 16.49 μg/g and 21.61 μg/g, respectively. Results from analysis of antioxidant and neuroprotective activity of the polysaccharides revealed that Se-RLFPs had a radical scavenging effect. Specifically, they effectively protected SH-SY5Y cells from H₂O₂-induced damage by enhancing antioxidant enzyme activities (SOD), total antioxidant capacity (T-AOC) and suppressing malondialdehyde (MDA) levels. Western blots showed that the underlying mechanisms of action may be related to the Nrf2/HO-1 signaling pathway. Taken together, these results suggested that Se-RLFPs have potential as a pharmaceutical agent for treatment of neurodegenerative diseases (NDDs) or as a selenium-complementary ingredient in functional foods.

Recent Advances in the Treatment of Insulin Resistance Targeting Molecular and Metabolic Pathways: Fighting a Losing Battle?

Diabetes Mellitus (DM) is amongst the most notable causes of years of life lost worldwide and its prevalence increases perpetually. The disease is characterized as multisystemic dysfunctions attributed to hyperglycemia resulting directly from insulin resistance (IR), inadequate insulin secretion, or enormous glucagon secretion. Insulin is a highly anabolic peptide hormone that regulates blood glucose levels by hastening cellular glucose uptake as well as controlling carbohydrate, protein, and lipid metabolism. In the course of Type 2 Diabetes Mellitus (T2DM), which accounts for nearly 90% of all cases of diabetes, the insulin response is inadequate, and this condition is defined as Insulin Resistance. IR sequela include, but are not limited to, hyperglycemia, cardiovascular system impairment, chronic inflammation, disbalance in oxidative stress status, and metabolic syndrome occurrence. Despite the substantial progress in understanding the molecular and metabolic pathways accounting for injurious effects of IR towards multiple body organs, IR still is recognized as a ferocious enigma. The number of widely available therapeutic approaches is growing, however, the demand for precise, safe, and effective therapy is also increasing. A literature search was carried out using the MEDLINE/PubMed, Google Scholar, SCOPUS and Clinical Trials Registry databases with a combination of keywords and MeSH terms, and papers published from February 2021 to March 2022 were selected as recently published papers. This review paper aims to provide critical, concise, but comprehensive insights into the advances in the treatment of IR that were achieved in the last months.