Herbal Active Ingredients: Potential for the Prevention and Treatment of Acute Lung Injury.

Acute lung injury (ALI) is a life-threatening clinical syndrome with high morbidity and mortality. The main pathological features of ALI are increased alveolar-capillary membrane permeability, edema, uncontrolled migration of neutrophils to the lungs, and diffuse alveolar damage, resulting in acute hypoxemic respiratory failure. Glucocorticoids, aspirin, and other anti-inflammatory drugs are commonly used to treat ALI. Respiratory supports, such as a ventilator, are used to alleviate hypoxemia. Many treatment methods are available, but they cannot significantly ameliorate the quality of life of patients with ALI and reduce mortality rates. Herbal active ingredients, such as flavonoids, terpenoids, saponins, alkaloids, and quinonoids, exhibit advantages for ALI prevention and treatment, but the underlying mechanism needs further study. This paper summarizes the role of herbal active ingredients in anti-ALI therapy and progresses in the understanding of their mechanisms. The work also provides some references and insights for the discovery and development of novel drugs for ALI prevention and treatment.

A novel polysaccharide from Dendrobium devonianum serves as a TLR4 agonist for activating macrophages.

Dendrobium devonianum has been used as herbal medicines and nutraceutical products since ancient time in China. However, its chemical composition and pharmacological mechanisms are not fully known. In present studies, by chemical purification and characteristic identification, we discovered a novel polysaccharide from D. devonianum, which was designated as DvP-1 with molecular weights of 9.52 × 104 Da. DvP-1 is a homogeneous heteropolysaccharide consisting of D-mannose and d-glucose in the molar ration of 10.11: 1. The main glycosidic linkages were ß-1, 4-Manp, which were substituted with acetyl groups at the O-2, O-3 and/or O-6 positions. DvP-1 was found to directly stimulate the activation of macrophages in vitro, as evidenced by inducing morphologic change, thereby promoting the production of cytokines TNF-α, IL-6 and NO, and enhancing the pinocytic activity of macrophages. By establishing a zebrafish model, we also found that DvP-1 could alleviate vinorelbine-induced decrease of macrophages in vivo. Further findings indicated that DvP-1 activated macrophages through several toll-like receptors (TLRs), but mainly through TLR4. DvP-1 served as a TLR4 agonist and induced ERK, JNK, p38, and IκB-α phosphorylation, suggesting the activation of MAPK and NFκB signaling pathways downstream of TLR4. These findings could help us further understand the immunomodulating effects of D. devonianum in Chinese medicines or health foods for immunocompromised persons. They also show the medicinal value of DvP-1 for the treatment of cancer and infectious diseases caused by TLR4 dysfunction.

Protective effect of Lycium barbarum on doxorubicin-induced cardiotoxicity.

The objective of this work was to explore the hypothesis that Lycium barbarum (LB) may be protective against doxorubicin (DOX)-induced cardiotoxicity through antioxidant-mediated mechanisms. Male SD rats were treated with distilled water or a water extract of LB (25 mg/kg, p.o.) daily and saline or DOX (5 mg/kg, i.v.) weekly for 3 weeks. Mortality, general condition and body weight were observed during the experiment. DOX-induced cardiotoxicity was assessed by electrocardiograph, heart antioxidant activity, serum levels of creatine kinase (CK) and aspartate aminotransferase (AST) and histopathological change. The DOX group showed higher mortality (38%) and worse physical characterization. Moreover, DOX caused myocardial injury manifested by arrhythmias and conduction abnormalities in ECG (increased QT and ST intervals and ST elevation), a decrease of heart antioxidant activity, an increase of serum CK and AST, as well as myocardial lesions. Pretreatment with LB significantly prevented the loss of myofibrils and improved the heart function of the DOX-treated rats as evidenced from lower mortality (13%), normalization of antioxidative activity and serum AST and CK, as well as improving arrhythmias and conduction abnormalities. These results suggested that LB elicited a typical cardioprotective effect on DOX-related oxidative stress. Furthermore, in vitro cytotoxic study showed the antitumor activity of DOX was not compromised by LB. It is possible that LB could be used as a useful adjunct in combination with DOX chemotherapy.