Progesterone Aggravates Lung Fibrosis in a Mouse Model of Systemic Sclerosis.

Background: Gender-related factors have explained the higher prevalence of autoimmune diseases in women. Sex hormones play a key role in the immune system and parenchymal cells function; therefore, these hormones can be important in the pathogenesis of autoimmune diseases as a risk or beneficial factor. Lung fibrosis is the main cause of mortality in systemic sclerosis, a female predominant autoimmune disease. The objective of this study was to examine the effect of progesterone on lung fibrosis in a mouse model of systemic sclerosis. Methods: Mice with bleomycin-induced lung fibrosis treated with progesterone subcutaneously for 21 and 28 days. Blood was collected for hormone and cytokine measurement at the end of treatment then, skin and lung tissues were harvested for histological assessment, gene expression, cytokine, hydroxyproline, and gelatinase measurement. Results: Trichrome staining and hydroxyproline measurements showed that progesterone treatment increased the content of collagen in fibrotic and normal lung tissues. Progesterone increased α-SMA (P < 0.01), TGF- ß (P < 0.05) and decreased MMP9 (P < 0.05) in fibrotic lung tissues. Also progesterone treatment decreased the gene expression of Col1a2 (P <0.05), Ctgf (P <01), End1 (0.001) in bleomycin- injured lung tissues. The serum level of TNF-α was decreased, but the serum level of cortisol was increased by progesterone treatment in fibrotic mice (P< 0.05). Conclusion: Our results showed that progesterone aggravates lung fibrosis in a mouse model of systemic sclerosis.

Implications the Role of miR-155 in the Pathogenesis of Autoimmune Diseases.

MicroRNAs (miRNAs) are small noncoding conserved RNAs containing 19 to 24 nucleotides that are regulators of post-translational modifications and are involved in the majority of biological processes such as immune homeostasis, T helper cell differentiation, central and peripheral tolerance, and immune cell development. Autoimmune diseases are characterized by immune system dysregulation, which ultimately leads to destructive responses to self-antigens. A large body of literature suggests that autoimmune diseases and immune dysregulation are associated with different miRNA expression changes in the target cells and tissues of adaptive or innate immunity. miR-155 is identified as a critical modulator of immune responses. Recently conducted studies on the expression profile of miR-155 suggest that the altered expression and function of miR-155 can mediate vulnerability to autoimmune diseases and cause significant dysfunction of the immune system.

In vitro anti-cancer efficacy of multi-functionalized magnetite nanoparticles combining alternating magnetic hyperthermia in glioblastoma cancer cells.

Localized hyperthermia and the targeted release of the chemotherapy drug are one of the most challenging problems in chemo-hyperthermia therapy. In the present study, magnetite nanoparticles as a carrier of Temozolomide (TMZ) functionalized with folic acid-ligand (TMZ-MNP-FA) were designed and developed for targeted chemotherapy and radiofrequency hyperthermia of cancer cells. Nanoparticles were synthesized and characterized for hydrodynamic diameter, zeta potential, morphology, drug loading capacity, and in vitro RF-triggered release. Their cytotoxicity and efficacy as targeted drug delivery systems were evaluated in both cancer and normal cells and the therapeutic efficacy was analyzed on the C6 glioblastoma cancer cells. The C6 cells were treated with the nanoparticles and subjected to an alternating magnetic field (AMF) to reach a typical hyperthermia temperature of 43 °C. Then induction of apoptotic cells and the proliferation capacity of cancer cells were evaluated. The in vitro release studies exhibited that the drug release from TMZ-loaded magnetite nanoparticles was minimal at 37 °C but was noticeably boosted under an AMF irradiation. The developed targeted magnetite nanoparticles revealed higher cytotoxic effect and cellular uptake in folate-receptor overexpressing C6 cancer cells compared to OLN-93 normal cells. All results showed that combined magnetite chemo-hyperthermia (AMF + TMZ-MNP-FA) treatment was significantly more efficacious in cancer cells than hyperthermia, chemotherapy, or chemo-hyperthermia treatments (P < 0.0001). In conclusion, TMZ-MNP-FA had a key role to convert the externally delivered radiofrequency energy to heat in cancer cells. Additionally, localized hyperthermia triggered a TMZ release from the nanocarriers that resulted in cancer cell damage with synchronizing hyperthermia and chemotherapy.

The Role of Progesterone in Cellular Apoptosis of Skin and Lung in a Bleomycin-injured Mouse Model.

Systemic sclerosis is a female predominant, a fibrotic autoimmune disease in which disturbance in tissue homeostasis and cell turnover including cell apoptosis are central events in pathogenesis. Sex hormones are known as the important players in sexual dimorphism of autoimmune diseases and in tissue homeostasis. Progesterone influences autoimmune disease via its immunomodulatory effect or by its direct action on parenchymal cell function. On the other hand, this hormone impacts tissue homeostasis by acting on cell apoptosis in a different situation. The objective of this study was to examine the effect of progesterone on cellular apoptosis of skin and lung tissues in a mouse model of scleroderma. Four group of mice were involved in this study with 10 mice in each. The fibrotic model was induced by daily subcutaneous injection of bleomycin for 28 days. One week after initiation of fibrosis induction, mice received subcutaneous progesterone alone or with bleomycin for 21 days. Control group received only Phosphate buffered saline PBS. After 28 days, under lethal anesthesia skin and lung tissues were harvested for histological assessment and hydroxyproline measurement. Apoptosis in tissue sections was detected by TUNEL assay technique. Bleomycin administration induced fibrosis in skin and lung tissues. Severe apoptosis was seen in skin and lung tissues of the bleomycin-treated group (p<0.001 in the skin and p<0.05 in the lung). Progesterone injection either in the skin (p>0.05) or in the lung (p>0.05) did not alter apoptosis in bleomycin-treated animals. Our data confirm the role of apoptosis in the pathogenesis of fibrosis in this model; however, progesterone does not affect cellular apoptosis in skin and lung tissues of bleomycin-injured animals.