G. N. Zyuz’kov

Involvement of PI3K, MAPK ERK1/2 and p38 in Functional Stimulation of Mesenchymal Progenitor Cells by Alkaloid Songorine

We studied the role of intracellular signaling molecules PI3K, МАРK ERK1/2, and р38 in stimulation of realization of the growth potential of mesenchymal progenitor cells by alkaloid songorine in vitro. Inhibitors of PI3K, ERK1/2 and р38 canceled the increase in proliferative activity of progenitor cells, the blockers of ERK1/2 and р38 reduced the intensity of progenitor cell differentiation.

Cerebroprotective and Regenerative Effects of Alkaloid Z77 under Conditions of Brain Ischemia

We studied the psychopharmacological effects of atisine-type diterpene alkaloid Z77 in a rat model of cerebral ischemia. Pronounced cerebroprotective effect was found consisting in normalization of the orienting and exploratory activity and conditioned behavior associated with significant correction of morphological changes in the brain. The direct stimulatory effect of Z77 on neural stem cells was shown in vitro.

Role of cAMP- and IKK-2-Dependent Signaling Pathways in Functional Stimulation of Mesenchymal Progenitor Cells with Alkaloid Songorine

The role of cAMP- and IKK-2-dependent pathways in stimulation of the growth capacity of mesenchymal progenitor cells with alkaloid songorine was studied in vitro. Inhibitors of adenylate cyclase and IKK-2 were shown to abolish the increase in proliferative activity of progenitor cells. Moreover, blockade of the inhibitory kinase complex was accompanied by a decrease in the intensity of progenitor cell differentiation.

Involvement of JAK1, JAK2, and JAK3 in Stimulation of Functional Activity of Mesenchymal Progenitor Cells by Fibroblast Growth Factor

We studied the involvement of individual JAK kinases in the realization of the growth potential of mesenchymal precursors under the effect of fibroblast growth factor. The important role of JAK2 and JAK3 in determining the initial level of mitotic activity of progenitor cells and participation of JAK1 in this process under conditions of cytokine stimulation of progenitor cells were demonstrated. Specific inhibitors of these kinases reduced the yield of fibroblast CFU and the rate of their division. Moreover, blockade of JAK1, JAK2, and JAK3 under the effect of fibroblast growth factor was accompanied by an increase in the intensity of progenitor cell differentiation.

Role of NF-κB/IKK-Dependent Signaling in Functional Stimulation of Mesenchymal Progenitor Cells by Alkaloid Songorine

We studied the role of NF-κB/IKK-mediated signaling in the stimulation of growth potential of mesenchymal progenitor cells by alkaloid songorine in vitro. Specific NF-κB inhibitor oridonin abolished activation of proliferation and differentiation of progenitor cells. Aurothiomalate, a selective blocker of IKK-2, also suppressed mitotic activity of fibroblast precursors, but had no effect on the rate of the differentiation.

Role of JNK and Contribution of p53 to the Realization of the Growth Potential of Mesenchymal Precursor Cells under the Effect of Fibroblast Growth Factor

The role of JNK-mediated signal pathway and participation of p53 transcription factor in stimulation of mesenchymal precursor cell function by the fibroblast growth factor was studied. The levels of fibroblast colony- and cluster formation and proliferative activity of mesenchymal precursors increased in response to JNK and p53 specific inhibitors. JNK and p53 blockers did not change the rate of fibroblast growth factor-induced progenitor element differentiation.

Antitumor Effects of JAK3 Inhibitor on the Model of Transplantable Lewis Lung Carcinoma and Mechanisms of Their Development

Mice with Lewis lung carcinoma were used to study the antitumor and antimetastatic effects of JAK3 inhibitor. The study revealed no effect of JAK3 inhibitor on the growth of primary tumor node, but found a pronounced inhibition of hematogenous spread of the pathologic process into the lungs. In vitro blockade of JAK3 in cultured Lewis lung carcinoma produced no effect on the count of the stem tumor cells and stimulated functions of committed elements. In addition, blockade of JAK3 significantly elevated maturation index of the tumor tissue.

Role of JNK and Contribution of p53 into Growth Potential of Mesenchymal Progenitor Cells In Vitro

Specifi c JNK and p53 inhibitors stimulated the formation of fi broblast colonies (CFU-F) and clusters (ClFU-F) and increased proliferative activity of mesenchymal progenitor cells. No effects of inhibitors of JNK and p53 on differentiation of progenitor elements were revealed.

Implication of JAK1, JAK2, and JAK3 in the Realization of Proliferation and Differentiation Potential of Mesenchymal Progenitor Cells In Vitro.

Involvement of individual JAK kinases in the realization of growth potential of mesenchymal progenitor cells was examined in vitro. Important role of JAK2 and JAK3 in determining the initial level of mitotic activity of progenitor cells was established. The yield of fibroblast CFUF was suppressed under the effect of specific inhibitors of JAK kinases. Blockade of JAK3 increased the rate of progenitor element differentiation. JAK1 had no effect on proliferation and differentiation status of progenitor cells.

Particular Role of JAK/STAT3 Signaling in Functional Control of Mesenchymal Progenitor Cells

The role of JAK/STAT3-mediated signaling pathway in the realization of the growth potential of mesenchymal precursor cells was examined in vitro. The stimulating role of JAKs and STAT3 towards proliferating activity of progenitor cells and their different role in the regulation of differentiation of the progenitor elements were demonstrated. Inhibitors of JAKs and STAT3 reduced the yield of fibroblast CFU and their mitotic activity. Blockade of JAKs accelerated and selective inactivation of STAT3 decelerated differentiation of progenitor cells.