Anti-Hyperglycemic Effect of a Kudzu (Pueraria lobata) Vine Extract in Ovariectomized Mice

Antioxidant and Cytotoxic Activities of Kudzu Roots and Soy Molasses against Pediatric Tumors and Phytochemical Analysis of Isoflavones Using HPLC-DAD-ESI-HRMS

Pediatric solid tumors (PSTs) are life-threatening and can lead to high morbidity and mortality rates in children. Developing novel remedies to treat these tumors, such as glioblastoma multiforme and sarcomas, such as osteosarcoma, and rhabdomyosarcoma, is challenging, despite immense attempts with chemotherapeutic or radiotherapeutic interventions. Soy (Glycine max) and kudzu roots (KR) (Pueraria spp.) are well-known phytoestrogenic botanical sources that contain high amounts of naturally occurring isoflavones. In the present study, we investigated the antioxidant and cytotoxic effects of the extracts of KR and soy molasses (SM) against PSTs. The green extraction of isoflavones from KR and SM was performed using natural deep eutectic solvents. The extracts were subsequently analyzed by high-performance liquid chromatography (HPLC)-diode array detector (DAD) coupled with high-resolution (HR) mass spectrometry (MS), which identified 10 isoflavones in KR extracts and 3 isoflavones in the SM extracts. Antioxidant and cytotoxic activities of KR and SM extracts were assessed against glioblastoma multiforme (A-172), osteosarcoma (HOS), and rhabdomyosarcoma (Rd) cancer cell lines. The KR and SM extracts showed satisfactory cytotoxic effects (IC₅₀) against the cancer cell lines tested, particularly against Rd cancer cell lines, in a dose-dependent manner. Antioxidant activity was found to be significantly (p ≤ 0.05) higher in KR than in SM, which was consistent with the results of the cytotoxic activity observed with KR and SM extracts against glioblastoma and osteosarcoma cells. The total flavonoid content and antioxidant activities of the extracts were remarkably attributed to the isoflavone content in the KR and SM extracts. This study provides experimental evidence that HPLC-ESI-HRMS is a suitable analytical approach to identify isoflavones that exhibit potent antioxidant and anticancer potential against tumor cells, and that KR and SM, containing many isoflavones, can be a potential alternative for health care in the food and pharmaceutical industries.

Potential therapeutic interventions of plant-derived isoflavones against acute lung injury

Acute lung injury (ALI) is a life-threatening syndrome that possibly leads to high morbidity and mortality as no therapy exists. Several natural ingredients with negligible adverse effects have recently been investigated to possibly inhibit the inflammatory pathways associated with ALI at the molecular level. Isoflavones, as phytoestrogenic compounds, are naturally occurring bioactive compounds that represent the most abundant category of plant polyphenols (Leguminosae family). A broad range of therapeutic activities of isoflavones, including antioxidants, chemopreventive, anti-inflammatory, antiallergic and antibacterial potentials, have been extensively documented in the literature. Our review exclusively focuses on the possible anti-inflammatory, antioxidant role of botanicals'-derived isoflavones against ALI and their immunomodulatory effect in experimentally induced ALI. Despite the limited scope covering their molecular mechanisms, isoflavones substantially contributed to protecting from ALI via inhibiting toll-like receptor 4 (TLR4)/Myd88/NF-κB pathway and subsequent cytokines, chemokines, and adherent proteins. Nonetheless, future research is suggested to fill the gap in elucidating the protective roles of isoflavones to alleviate ALI concerning antioxidant potentials, inhibition of the inflammatory pathways, and associated molecular mechanisms.

Ameliorative Effects of Pueraria lobata Extract on Postmenopausal Symptoms through Promoting Estrogenic Activity and Bone Markers in Ovariectomized Rats

Pueraria lobata (Willd.) Ohwi, known as kudzu, is one of the most popular traditional medicines in Asian countries. It has been widely used as a natural alternative to hormone replacement therapy for treating postmenopausal symptoms. This study aimed to investigate the estrogenic effect of P. lobata extract (PE) against postmenopausal osteoporosis in ovariectomized (OVX) rats. OVX rats were treated with PE (25–1600 mg/kg) for 8 weeks. Biochemical parameters, estradiol, and bone turnover markers (e.g., osteocalcin, C-terminal telopeptide fragment of type I collagen, deoxypyridinoline, and pyridinoline) were measured in plasma samples. In addition, estrogen receptor-alpha (ER-α) protein expression and morphology of uterine were evaluated. Long-term treatment with PE did not cause liver damage in OVX rats. PE supplementation reduced body weight gain in obese rats with high lipid accumulation induced by ovariectomy. Furthermore, PE exhibited a protective effect against insulin resistance, hyperlipidemia, and hepatic lipid peroxidation. PE treatment increased uterine weight and thickness of the uterine layers in cases of uterus atrophy due to removal of ovaries. The levels of bone turnover markers, which were significantly increased in OVX rats, were decreased by PE treatment. Western blotting analysis showed that ER-α protein expression was upregulated in PE-treated rats compared with OVX rats. These results suggest that PE could be a promising alternative functional food for improving menopausal symptoms.

Isoflavones derived from plant raw materials: bioavailability, anti-cancer, anti-aging potentials, and microbiome modulation

Isoflavones are secondary metabolites that represent the most abundant category of plant polyphenols. Dietary soy, kudzu, and red clover contain primarily genistein, daidzein, glycitein, puerarin, formononetin, and biochanin A. The structural similarity of these compounds to β-estradiol has demonstrated protection against age-related and hormone-dependent diseases in both genders. Demonstrative shreds of evidence confirmed the fundamental health benefits of the consumption of these isoflavones. These relevant activities are complex and largely driven by the source, active ingredients, dose, and administration period of the bioactive compounds. However, the preclinical and clinical studies of these compounds are greatly variable, controversial, and still with no consensus due to the non-standardized research protocols. In addition, absorption, distribution, metabolism, and excretion studies, and the safety profile of isoflavones have been far limited. This highlights a major gap in understanding the potentially critical role of these isoflavones as prospective replacement therapy. Our general review exclusively focuses attention on the crucial role of isoflavones derived from these plant materials and critically highlights their bioavailability, possible anticancer, antiaging potentials, and microbiome modulation. Despite their fundamental health benefits, plant isoflavones reveal prospective therapeutic effects that worth further standardized analysis.

Subacute oral toxicity and bacterial mutagenicity of a mixture of Puerariae radix and Hizikia fusiforme extracts

The study aims to identify the safety profile of a mixed extract (KGC-02-PS) from two traditional medicinal herbs, Puerariae radix and Hizikia fusiforme. In a subacute oral toxicity study, KGC-02-PS was administered orally for 28 days by gavage to Sprague Dawley rats (both sexes) at a daily dose of 0, 500, 1000, and 2000 mg/kg body weight. Bodyweight, food consumption, and clinical signs were monitored during the experimental period. After administering the final dose, this study conducted hematology, serum biochemistry, and pathological evaluations. In addition, the study performed a bacterial reverse mutation test with varying concentrations of KGC-02-PS (312.5 μg - 5,000 μg/plate) following OECD guideline No. 471, before testing five bacterial strains (Salmonella typhimurium TA98, TA100, TA1535, TA1537, and Escherichia coli WP2) in the presence or absence of metabolic activation. The preclinical evaluation of KGC-02-PS's subacute oral toxicity yielded no associated toxicological effects or any changes in clinical signs, body weight, and food consumption. Moreover, examining KGC-02-PS's hematological and serum biochemical characteristics and pathology yielded no toxicological changes in terms of organ weight measurements and gross or histopathological findings. KGC-02-PS neither increased the number of revertant colonies in all bacterial strains used in the bacterial reverse mutation test, nor did it induce genotoxicity related to bacterial reverse mutations under the study's conditions. Also, KGC-02-PS's no-observed-adverse-effect level was greater than 2000 mg/kg.

Puerarin blocks the aging phenotype in human dermal fibroblasts

Dermal fibroblast aging contributes to aging-associated functional defects in the skin since dermal fibroblasts maintain skin homeostasis by interacting with the epidermis and extracellular matrix. Here, we found that puerarin, an isoflavone present in Pueraria lobata (Kudzu), can prevent the development of the aging-phenotype in human dermal fibroblasts. Normal human dermal fibroblasts (NHDFs) were subcultivated and high-passage cells were selected as senescent cells, whereas low-passage cells were selected as a young cell control. Puerarin treatment increased cell proliferation and decreased the proportion of senescence-associated beta-galactosidase-positive cells in a high-passage culture of NHDFs. Moreover, puerarin treatment reduced the number of smooth muscle actin (SMA)-positive myofibroblasts and the expression of a reticular fibroblast marker, calponin 1 (CNN1), which were induced in high-passage NHDFs. Fulvestrant, an estrogen receptor antagonist, blocked the puerarin-mediated downregulation of SMA and CNN1. Our results suggest that puerarin may be a useful functional food that alleviates aging-related functional defects in dermal fibroblasts.

Puerarin ameliorates skeletal muscle wasting and fiber type transformation in STZ-induced type 1 diabetic rats

Puerarin is an isoflavonoid extracted from Pueraria lobate with extensive pharmacological effects in traditional Chinese medicine. The evidence implicates that puerarin mitigates hyperglycemia and various relevant complications. Here, the effect of puerarin on skeletal muscle wasting induced by type 1 diabetes (T1D) was explored. Streptozotocin (STZ)-induced T1D male Sprague Dawley (SD) rats were used in this study. Muscle strength, weight and size were measured. L6 rat skeletal muscle cells were applied for in vitro study. Our results showed that eight-week oral puerarin administration (100 mg/kg) increased muscle strengths and weights accompanied by enhanced skeletal muscle cross-sectional areas in diabetic rats. Simultaneously, puerarin also reduced expressions of several muscle wasting marker genes including F-box only protein 32 (Atrogin-1) and muscle-specific RING-finger 1 (Murf-1) in diabetic group both in vitro and in vivo. Transformation from type I fibers (slow muscle) to type II fibers (fast muscle) were also observed under puerarin administration in diabetic rats. Puerarin promoted Akt/mTOR while inhibited LC3/p62 signaling pathway in skeletal muscle cells. In conclusion, our study showed that puerarin mitigated skeletal muscle wasting in T1D rats and closely related with Akt/mTOR activation and autophagy inhibition. Whether this effect in murine applies to humans remains to be determined.

Agrimonia pilosa Ledeb. Ameliorates Hyperglycemia and Hepatic Steatosis in Ovariectomized Rats Fed a High-Fat Diet

Estrogen deficiency is associated with obesity, dyslipidemia, and increased insulin resistance in postmenopausal women. An efficient therapeutic agent prevents or improves postmenopausal conditions induced by estrogen deficiency. Here, we investigated the effects of aqueous Agrimonia pilosa Ledeb. extract on glucose and lipid metabolism in ovariectomized rats fed a high-fat diet (HFD). Female Sprague-Dawley rats were sham-operated or ovariectomized, and 3 weeks later were assigned to the following groups: sham-operated + HFD (S); ovariectomized + HFD (OVX); and ovariectomized + HFD with 0.5% A. pilosa aqueous extract (OVX + 0.5A) groups. Ovariectomy significantly increased body weight and dietary intake relative to the S group. However, A. pilosa treatment did not significantly affect weight gain or dietary intake. Blood triacylglycerol, total cholesterol, and low-density lipoprotein cholesterol levels tended to decrease in the A. pilosa-supplemented group. Blood glucose levels were significantly lower in the OVX + 0.5A group than those in the OVX group. Blood adiponectin and insulin concentrations increased significantly after A. pilosa treatment in the ovariectomized group. A. pilosa supplementation tended to decrease liver weights and prevented lipid accumulation. These effects correlated with reduced hepatic expression of lipogenesis-related genes (fatty acid synthase, acetyl-coenzyme A carboxylase alpha, and 3-hydroxy-3-methylglutaryl-coenzyme A reductase). Therefore, A. pilosa may improve metabolic disorders in ovariectomized rats.

Management of Diabetes Mellitus with Puerarin, a Natural Isoflavone FromPueraria lobata

Diabetes mellitus (DM) has become one of the most challenging public health problems globally. The increasing prevalence and mortality rates call for more effective therapeutic agents, especially for DM complications. Traditional herbs have a long clinical application history for DM treatment. Puerarin is a natural isoflavone from Pueraria lobata (Wild.) Ohwi which has been consumed both as a functional food and herb in Eastern Asia countries. Documented data has shown that puerarin has cardio-protective, neuroprotective, anti-oxidative, anti-inflammatory and many other effects. In this review, we will summarize the beneficial effects and underlying mechanisms of puerarin on DM and complications. Puerarin may directly benefit DM by decreasing blood glucose levels, improving insulin resistance, protecting islets, inhibiting inflammation, decreasing oxidative stress and inhibiting Maillard reaction and advanced glycation end products (AGEs) formation. Furthermore, puerarin may also benefit DM indirectly by retarding and improving a series of DM complications, such as cardiovascular complications, diabetic nephropathy, diabetic retinopathy, diabetic neuropathy, etc. However, comprehensive studies of its effect and mechanisms are needed. In addition, its efficacy is relatively low, which is partially due to its pharmacokinetics profiles. Though puerarin shows low toxicity to experimental animals, its safety on human remains to be clarified. Collectively, we suggest that puerarin might be a potential adjuvant agent for the treatment of DM and DM complications in future.

Selenium-layered nanoparticles serving for oral delivery of phytomedicines with hypoglycemic activity to synergistically potentiate the antidiabetic effect

Diabetes mellitus (DM) remains a great challenge in treatment due to pathological complexity. It has been proven that phytomedicines and natural medicines have prominent antidiabetic effects. This work aimed to develop selenium-layered nanoparticles (SeNPs) for oral delivery of mulberry leaf and Pueraria Lobata extracts (MPE), a group of phytomedicines with significant hypoglycemic activities, to achieve a synergic antidiabetic effect. MPE-loaded SeNPs (MPE-SeNPs) were prepared through a solvent diffusion/in situ reduction technique and characterized by particle size, ζ potential, morphology, entrapment efficiency (EE) and drug loading (DL). The resulting MPE-SeNPs were 120 nm around in particle size with EE of 89.38% for rutin and 90.59% for puerarin, two marker components in MPE. MPE-SeNPs exhibited a slow drug release and good physiological stability in the simulated digestive fluid. After oral administration, MPE-SeNPs produced significant hypoglycemic effects both in the normal and diabetic rats. Ex vivo intestinal imaging and cellular examinations demonstrated that MPE-SeNPs were provided with outstanding intestinal permeability and transepithelial transport aptness. It was also revealed that MPE-SeNPs could alleviate the oxidative stress, improve the pancreatic function, and promote the glucose utilization by adipocytes. Our study provides new insight into the use of integrative nanomedicine containing phytomedicines and selenium for DM treatment.

Herbal formula SC-E1 suppresses lipopolysaccharide-stimulated inflammatory responses through activation of Nrf2/HO-1 signaling pathway in RAW 264.7 macrophages

BACKGROUND

SC-E1 is a novel herbal formula consisting of five oriental medicinal herbs used frequently in traditional herbal medicine for the treatment of inflammatory diseases in Korea. This study examined the effects of SC-E1 on lipopolysaccharide (LPS)-stimulated macrophages and the molecular mechanism involved.

METHODS

The cytotoxic effect of the SC-E1 extract was evaluated in RAW 264.7 cells by MTT assay. The effects of SC-E1 on the free radical scavenging and generation of intracellular reactive oxygen species were measured using DPPH and DCFH-DA, respectively. The effects of SC-E1 on the production of pro-inflammatory cytokines, inflammatory mediators, and related products were determined by ELISA and western blotting. The molecular mechanism and the nuclear translocation of nuclear factor-kappa B (NF-κB) and NF-E2-related factor 2 (Nrf2) were examined by western blot analysis and immunocytochemistry.

RESULTS

SC-E1 exhibited strong anti-oxidant activity and inhibited LPS-induced NO secretion as well as iNOS expression and the production of pro-inflammatory cytokines, without affecting the cell viability. SC-E1 also suppressed the LPS-induced NF-κB activation and the mitogen-activated protein kinase (MAPK) pathway. Moreover, SC-E1 induced heme oxygenase-1 (HO-1) expression via the nuclear translocation of Nrf2. The inhibitory effects of SC-E1 on the production of pro-inflammatory cytokines were abrogated by treatment with SnPP, an HO-1 inhibitor.

CONCLUSION

These results suggest that SC-E1 exerts its anti-oxidant and anti-inflammatory effects through the inhibition of NF-κB and MAPK as well as Nrf2-mediated HO-1 induction in macrophages. These findings provide evidences for SC-E1 to be considered as a new prescription for treating inflammatory diseases.