Insulin Treatment Forces Arteriogenesis in Diabetes Mellitus by Upregulation of the Early Growth Response-1 (Egr-1) Pathway in Mice.

The process of arteriogenesis is severely compromised in patients with diabetes mellitus (DM). Earlier studies have reported the importance of Egr-1 in promoting collateral outward remodeling. However, the role of Egr-1 in the presence of DM in outward vessel remodeling was not studied. We hypothesized that Egr-1 expression may be compromised in DM which may lead to impaired collateral vessel growth. Here, we investigated the relevance of the transcription factor Egr-1 for the process of collateral artery growth in diabetic mice. Induction of arteriogenesis by femoral artery ligation resulted in an increased expression of Egr-1 on mRNA and protein level but was severely compromised in streptozotocin-induced diabetic mice. Diabetes mellitus mice showed a significantly reduced expression of Egr-1 endothelial downstream genes Intercellular Adhesion Molecule-1 (ICAM-1) and urokinase Plasminogen Activator (uPA), relevant for extravasation of leukocytes which promote arteriogenesis. Fluorescent-activated cell sorting analyses confirmed reduced leukocyte recruitment. Diabetes mellitus mice showed a reduced expression of the proliferation marker Ki-67 in growing collaterals whose luminal diameters were also reduced. The Splicing Factor-1 (SF-1), which is critical for smooth muscle cell proliferation and phenotype switch, was found to be elevated in collaterals of DM mice. Treatment of DM mice with insulin normalized the expression of Egr-1 and its downstream targets and restored leukocyte recruitment. SF-1 expression and the diameter of growing collaterals were normalized by insulin treatment as well. In summary, our results showed that Egr-1 signaling was impaired in DM mice; however, it can be rescued by insulin treatment.

Morin and Esculetin supplementation modulates c-myc induced energy metabolism and attenuates neoplastic changes in rats challenged with the procarcinogen 1,2 - dimethylhydrazine.

Targeting tumor metabolism by natural products is a novel approach and provides rationale for anti-cancer drug discovery. The present study aims to explore the impact of morin and/or esculetin on c-myc induced energy metabolism in 1,2-dimethylhydrazine (DMH) induced colon cancer in rats. In order to achieve this aim we analyzed the expression of glucose and glutamine transporters and the key enzymes of glycolytic pathway besides the markers of neoplastic changes viz., mucin depleted foci (MDF), beta catenin accumulated crypts (BCAC), and markers of cell proliferation viz., proliferating cell nuclear antigen (PCNA), argyrophilic nucleolar antigen (AgNOR), c-myc, c-jun and c-fos. All the parameters tested in the present study are highly influenced by the phytochemicals morin and/or esculetin in a way to prevent colon carcinogenesis. Morin and/or esculetin supplementation effectively targets tumor metabolism via ß-cateinin/c-myc signaling and affects glycolysis and glutaminolysis to abrogate colon cancer in rats. The anti-cancer effect of morin is more pronounced than esculetin. The effect obtained through the combined treatment of morin and esculetin is comparable to that of individual supplementation of morin and there is no synergistic effect. Overall individual supplementation of morin scores well as a potential anticancer agent targeting glycolysis and glutaminolysis in colon cancer.

Terpenoids as anti-colon cancer agents - A comprehensive review on its mechanistic perspectives.

Multistep model of colon carcinogenesis has provided the framework to advance our understanding of the molecular basis of colon cancer. This multistage process of carcinogenesis takes a long period to transform from a normal epithelial cell to invasive carcinoma. Thus, it provides enough time to intervene the process of carcinogenesis especially through dietary modification. In spite of the in-depth understanding of the colon cancer etiology and pathophysiology and its association with diet, colon cancer remains a major cause of cancer mortality worldwide. Phytochemicals and their derivatives are gaining attention in cancer prevention and treatment strategies because of cancer chemotherapy associated adverse effects. Being the largest group of phytochemicals traditionally used for medicinal purpose in India and China, terpenoids are recently being explored as anticancer agents. Anticancer properties of terpenoids are associated with various mechanisms like counteraction of oxidative stress, potentiating endogenous antioxidants, improving detoxification potential, disrupting cell survival pathways and inducing apoptosis. This review gives a comprehensive idea of naturally occurring terpenoids as useful agents for the prevention of colon cancer with reference to their classes, sources and molecular targets. Based on the explored molecular targets further research in colon cancer chemoprevention is warranted.

Chemopreventive agents targeting tumor microenvironment.

Recent studies have shown that tumor development and progression depend not only on the perturbed genes that govern cell proliferation, but is also highly determined by the non-tumor cells of the stromal compartment surrounding the tumor called tumor microenvironment (TME). These findings highlight the importance of targeting the microenvironment in combination with therapies aimed at tumor cells as a valuable approach. The innate and adaptive immune cells in the TME interact among themselves and also with the endothelial cells, pericytes and mast cells of the stromal compartment through various autocrine and paracrine manner to regulate abnormal cell proliferation. Direct cytotoxic killing of cancer cells and/or reversion of the immunosuppressive TME are to be considered as better strategies for chemoprevention and chemotherapy. With a growing emphasis on a "hallmark targeting" strategy for cancer therapy, the TME now appears as a promising target for cancer prevention using natural products. Clarification on the nontumor stromal cells, the mediators involved, interactions with immune response cells, and immune-evasive mechanisms are needed in order to manipulate the characteristics of the TME by natural pharmacological agents to design effective therapies. This review will provide a glimpse on the roles played by various non-tumor cells in tumor progression and their intervention by pharmacological agents.

Ferulic acid pretreatment mitigates MPTP-induced motor impairment and histopathological alterations in C57BL/6 mice.

CONTEXT: Ferulic acid (FA) is a potent ubiquitous plant antioxidant found in cereals such as brown rice, whole wheat, and oats. Phytochemical-based antioxidants are shown to be effective in neurodegenerative diseases. This study hypothesizes that supplementation of FA might combat oxidative stress-induced Parkinson's disease (PD). OBJECTIVE: To explore the effect of FA on 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine hydrochloride (MPTP)-induced neurotoxicity. MATERIALS AND METHODS: Mice were randomized into five groups: Group I mice served as control. Group II mice received 5 × MPTP [25 mg/kg body weight (i.p.)] in saline 24 h apart starting from the 3rd day and continued till the last day of the experimental period of 7 d. In addition to MPTP injections, mice in Groups III, IV, and V were given FA at a dose of 20, 40, and 80 mg, respectively, for 7 d. Mice were subjected to a battery of behavioral tests along with histological investigations. RESULTS: Our histological findings revealed that MPTP administration enhanced Bax/Bcl2 ratio and microglial cells activation reflecting induction of apoptosis and inflammation, respectively. This dopaminergic neuronal loss caused impairment in motor balance and coordination in MPTP mice as assessed by various behavioral tests. FA at a dose of 40 mg/kg/d body weight effectively attenuated MPTP-induced neurotoxicity. DISCUSSION: Antioxidant, free-radical quenching, and anti-inflammatory activities of FA could contribute to its neuroprotective effect. CONCLUSION: This study provides elementary evidence for the neuroprotective action of FA against MPTP-induced PD in mice and warrants further studies.