Flexicaulin A, An ent-Kaurane Diterpenoid, Activates p21 and Inhibits the Proliferation of Colorectal Carcinoma Cells through a Non-Apoptotic Mechanism.

Natural products, explicitly medicinal plants, are an important source of inspiration of antitumor drugs, because they contain astounding amounts of small molecules that possess diversifying chemical entities. For instance, Isodon (formerly Rabdosia), a genus of the Lamiaceae (formerly Labiatae) family, has been reported as a rich source of natural diterpenes. In the current study, we evaluated the in vitro anti-proliferative property of flexicaulin A (FA), an Isodon diterpenoid with an ent-kaurane structure, in human carcinoma cells, by means of cell viability assay, flow cytometric assessment, quantitative polymerase chain reaction array, Western blotting analysis, and staining experiments. Subsequently, we validated the in vivo antitumor efficacy of FA in a xenograft mouse model of colorectal carcinoma. From our experimental results, FA appears to be a potent antitumor molecule, since it significantly attenuated the proliferation of human colorectal carcinoma cells in vitro and restricted the growth of corresponsive xenograft tumors in vivo without causing any adverse effects. Regarding its molecular mechanism, FA considerably elevated the expression level of p21 and induced cell cycle arrest in the human colorectal carcinoma cells. While executing a non-apoptotic mechanism, we believe the antitumor potential of FA opens up new horizons for the therapy of colorectal malignancy.

Advanced Glycation End-Product Precursor Methylglyoxal May Lead to Development of Alzheimer's Disease.

Introduction: Diabetes mellitus (DM) is characterized by chronic hyperglycemia and diabetic complications. Exacerbated cortical neuronal degeneration was observed in Alzheimer's disease (AD) patients with DM. In fact, DM is now considered a risk factor of AD, as DM-induced activation of stress responses in the central nervous system (CNS) such as oxidative stress and neuroinflammation may lead to various neurodegenerative disorders. Methylglyoxal (MG) is one of the most reactive advanced glycation end-product (AGE) precursors. Abnormal accumulation of MG is observed in the serum of diabetic patients. As MG is reported to promote brain cells impairment in the CNS, and it is found that AGEs are abnormally increased in the brains of AD patients. Therefore, the effect of MG causing subsequent symptoms of AD was investigated. Methods: 5-week-old C57BL/6 mice were intraperitoneally injected with MG solution for 11 weeks. The Morris water maze (MWM) was used to examine the spatial learning ability and cognition of mice. After MG treatment, MTT assay, real-time PCR analyses, and Western blot were performed to assess the harvested astrocytes and hippocampi. Results: Significantly longer escape latency and reduced percentage time spent in the target quadrant were observed in the 9-week-MG-treated mice. We have found in both in vitro and in vivo models that MG induced astrogliosis, pro-inflammatory cytokines, AD-related markers, and ERK activation. Further, trend of normalization of the tested markers mRNA expressions were observed after ERK inhibition. Conclusion: Our in vivo results suggested that MG could induce AD symptoms and in vitro results implied that ERK may regulate the promotion of inflammation and Aß formation in MG-induced reactive astrocytes. Taken together, MG may participate in the dysfunction of brain cells resulting in possible diabetes-related neurodegeneration by promoting astrogliosis, Aß production, and neuroinflammation through the ERK pathway. Our findings provide insight of targeting ERK as a therapeutic application for diabetes-induced AD.

An anti-inflammatory and anti-fibrotic proprietary Chinese medicine nasal spray designated as Allergic Rhinitis Nose Drops (ARND) with potential to prevent SARS-CoV-2 coronavirus infection by targeting RBD (Delta)- angiotensin converting enzyme 2 (ACE2) binding.

BACKGROUND: Since the outbreak of COVID-19 has resulted in over 313,000,000 confirmed cases of infection and over 5,500,000 deaths, substantial research work has been conducted to discover agents/ vaccines against COVID-19. Undesired adverse effects were observed in clinical practice and common vaccines do not protect the nasal tissue. An increasing volume of direct evidence based on clinical studies of traditional Chinese medicines (TCM) in the treatment of COVID-19 has been reported. However, the safe anti-inflammatory and anti-fibrotic proprietary Chinese medicines nasal spray, designated as Allergic Rhinitis Nose Drops (ARND), and its potential of re-purposing for suppressing viral infection via SARS-CoV-2 RBD (Delta)- angiotensin converting enzyme 2 (ACE2) binding have not been elucidated. PURPOSE: To characterize ARND as a potential SARS-CoV-2 entry inhibitor for its possible preventive application in anti-virus hygienic agent. METHODS: Network pharmacology analysis of ARND was adopted to asacertain gene targets which were commonly affected by COVID-19. The inhibitory effect of ARND on viral infection was determined by an in vitro pseudovirus assay. Furthermore, ARND was confirmed to have a strong binding affinity with ACE2 and SARS-CoV-2 spike-RBD (Delta) by ELISA. Finally, inflammatory and fibrotic cell models were used in conjunction in this study. RESULTS: The results suggested ARND not only inhibited pseudovirus infection and undermined the binding affinity between ACE2 and the Spike protein (Delta), but also attenuated the inflammatory response upon infection and may lead to a better prognosis with a lower risk of pulmonary fibrosis. The data in this study also provide a basis for further development of ARND as an antiviral hygienic product and further investigations on ARND in the live virus, in vivo and COVID-19 patients. ARND holds promise for use in the current COVID-19 outbreak as well as in future pandemics. CONCLUSION: ARND could be considered as a safe anti-SARS-CoV-2 agent with potential to prevent SARS-CoV-2 coronavirus infection.

Methylglyoxal activates osteoclasts through JNK pathway leading to osteoporosis.

Diabetes mellitus is characterized by chronic hyperglycemia and its diverse complications. Hyperglycemia is associated with inflammatory responses in different organs, and diabetic patients have a higher risk of bone fracture due to increased bone weakness. Methylglyoxal, a reactive advanced glycation end product precursor, is known to have increased level in diabetic patients. The accumulation of methylglyoxal promotes inflammation and it may play a role in diabetes related osteoporosis. In this study, therefore, the underlying mechanism of methylglyoxal on osteoporosis was studied using both animal and cell models. In the animal model, rats were treated with either methylglyoxal or saline as control. In the cell model, the macrophage RAW264.7 was treated with methylglyoxal or vehicle control. Following the treatment, animal samples were harvested for micro-CT and real-time polymerase chain reaction analyses. Cell samples were harvested for MTT assay, RT-PCR, and Western Blotting analyses. In both animals and cell cultures, methylglyoxal was shown to induce osteoclastogenesis by increased gene expression of osteoclast bone biomarkers CTSK, OSCAR and TRACP5. Furthermore, in methylglyoxal-treated macrophages activation of the c-Jun N-terminal kinases signaling pathway was observed, and inhibition of JNK activities resulted in down-regulation of osteoclast biomarkers gene expressions. Our results therefore suggested that methylglyoxal may contribute to the progression of diabetes-related osteoporosis and imbalanced bone remodeling through JNK pathway in osteoclasts.

The dataset of methylglyoxal activating p38 and p44/42 pathway in osteoclast.

Diabetes mellitus (DM) is a kind of chronic metabolic disease that could be characterized by uncontrollable high blood glucose (hyperglycemia) over a prolonged period and diverse complications in various organs. These complications include activation of stress responses in bone such as oxidative stress and inflammation, which have been implicated in various bone diseases, including osteoporosis. Non-enzymatic glycation of proteins form and accumulate in patients under hyperglycemia condition. Methylglyoxal (MG) is a reactive advanced glycation end-product precursor. Abnormal high concentration of MG was in serum of diabetic patients. It was proven that MG induces various stress responses. This indicates that it might possibly the key metabolite leading to diabetes-associated bone loss. In this data report, using cell models, the underlying mechanism of methylglyoxal on osteoclast that may lead to bone loss was investigated. In cell cultures, RAW264.7, Macrophages, was treated with methylglyoxal and gene expressions of osteoclast bone biomarkers were investigated. Furthermore, the inhibitions of p38 and p44/42 activities were employed to investigate the osteoclast biomarkers CTSK, OSCAR, and TRACP5 gene expressions. These data implied that MG activated the p38 and p44/42, which was reported to regulate proliferation and differentiation of osteoclast. However, the decreasing MAPK though siRNA knockdown did not change expression of those target markers, TRACP5, OSCAR, and CTSK, in mRNA level. The effects of MG to other osteoclast markers through p38 and p44/42 would be worth to be investigated. For more insight please see Methylglyoxal Activates Osteoclasts through JNK Pathway leading to Osteoporosis.

In Vitro and in Vivo Antitumor Effects of Plant-Derived Miliusanes and Their Induction of Cellular Senescence.

Our earliest phytochemical separation of Miliusa sinensis aided us in the isolation of a class of unique miliusanes, which were demonstrated as anticancer lead molecules. In the present study, we isolated 19 miliusanes (1-19), including 11 novel ones (5 and 10-19) from another Miliusa plant ( M. balansae), and synthesized additional derivatives to elucidate the structure-activity relationship of miliusanes. When extrapolated to various carcinoma xenograft mouse models, miliusol (1) and its derivatives 20, 26, and 27 (7.5-40 mg/kg) were demonstrated with tumor inhibitory efficacy comparable or even superior to the mainstay chemotherapeutics paclitaxel or fluorouracil. To gain a molecular insight into their anticancer mechanism, 1-3 (GI50 0.03-4.79) were administered to a wide spectrum of human cancer cell lines, including those with specific drug resistance. We further revealed that the antiproliferative properties of miliusanes in carcinoma cells were highly associated with the p21-dependent induction of cellular senescence.