Elevated α5 integrin expression on myeloid cells in motor areas in amyotrophic lateral sclerosis is a therapeutic target.

Amyotrophic lateral sclerosis (ALS) is a fatal disease affecting upper and lower motor neurons. Microglia directly interact with motor neurons and participate in the progression of ALS. Single-cell mass cytometry (CyTOF) analysis revealed prominent expression of α5 integrin in microglia and macrophages in a superoxide dismutase-1 G93A mouse model of ALS (SOD1G93A). In postmortem tissues from ALS patients with various clinical ALS phenotypes and disease duration, α5 integrin is prominent in motor pathways of the central and peripheral nervous system and in perivascular zones associated with the blood-brain barrier. In SOD1G93A mice, administration of a monoclonal antibody against α5 integrin increased survival compared to an isotype control and improved motor function on behavioral testing. Together, these findings in mice and in humans suggest that α5 integrin is a potential therapeutic target in ALS.

Tongxinluo attenuates oxygen-glucose-serum deprivation/restoration-induced endothelial barrier breakdown via peroxisome proliferator activated receptor-α/angiopoietin-like 4 pathway in high glucose-incubated human cardiac microvascular endothelial cells.

BACKGROUND: Traditional Chinese medicine Tongxinluo (TXL) has been widely used to treat coronary artery disease in China, since it could reduce myocardial infarct size and ischemia/reperfusion injury in both non-diabetic and diabetic conditions. It has been shown that TXL could regulate peroxisome proliferator activated receptor-α (PPAR-α), a positive modulator of angiopoietin-like 4 (Angptl4), in diabetic rats. Endothelial junction substructure components, such as VE-cadherin, are involved in the protection of reperfusion injury. Thus, we hypothesized cell-intrinsic and endothelial-specific Angptl4 mediated the protection of TXL on endothelial barrier under high glucose condition against ischemia/reperfusion-injury via PPAR-α pathway. METHODS: Incubated with high glucose medium, the human cardiac microvascular endothelial cells (HCMECs) were then exposed to oxygen-glucose-serum deprivation (2 hours) and restoration (2 hours) stimulation, with or without TXL, insulin, or rhAngptl4 pretreatment. RESULTS: TXL, insulin, and rhAngptl4 had similar protective effects on the endothelial barrier. TXL treatment reversed the endothelial barrier breakdown in HCMECs significantly as identified by decreasing endothelial permeability, upregulating the expression of JAM-A, VE-cadherin, and integrin-α5 and increasing the membrane location of VE-cadherin and integrin-α5, and these effects of TXL were as effective as insulin and rhAngptl4. However, Angptl4 knock-down with small interfering RNA (siRNA) interference and PPAR-α inhibitor MK886 partially abrogated these beneficial effects of TXL. Western blotting also revealed that similar with insulin, TXL upregulated the expression of Angptl4 in HCMECs, which could be inhibited by Angptl4 siRNA or MK886 exposure. TXL treatment increased PPAR-α activity, which could be diminished by MK886 but not by Angptl4 siRNA. CONCLUSION: These data suggest cell-intrinsic and endothelial-specific Angptl4 mediates the protection of TXL against endothelial barrier breakdown during oxygen-glucose-serum deprivation and restoration under high glucose condition partly via the PPAR-α/Angptl4 pathway.

Sulforaphane inhibits proliferation and invasive activity of everolimus-resistant kidney cancer cells in vitro.

Although the mechanistic target of rapamycin (mTOR) inhibitor, everolimus, has improved the outcome of patients with renal cell carcinoma (RCC), improvement is temporary due to the development of drug resistance. Since many patients encountering resistance turn to alternative/complementary treatment options, an investigation was initiated to evaluate whether the natural compound, sulforaphane (SFN), influences growth and invasive activity of everolimus-resistant (RCCres) compared to everolimus-sensitive (RCCpar) RCC cell lines in vitro. RCC cells were exposed to different concentrations of SFN and cell growth, cell proliferation, apoptosis, cell cycle, cell cycle regulating proteins, the mTOR-akt signaling axis, adhesion to human vascular endothelium and immobilized collagen, chemotactic activity, and influence on surface integrin receptor expression were investigated. SFN caused a significant reduction in both RCCres and RCCpar cell growth and proliferation, which correlated with an elevation in G2/M- and S-phase cells. SFN induced a marked decrease in the cell cycle activating proteins cdk1 and cyclin B and siRNA knock-down of cdk1 and cyclin B resulted in significantly diminished RCC cell growth. SFN also modulated adhesion and chemotaxis, which was associated with reduced expression of the integrin subtypes α5, α6, and ß4. Distinct differences were seen in RCCres adhesion and chemotaxis (diminished by SFN) and RCCpar adhesion (enhanced by SFN) and chemotaxis (not influenced by SFN). Functional blocking of integrin subtypes demonstrated divergent action on RCC binding and invasion, depending on RCC cell sensitivity to everolimus. Therefore, SFN administration could hold potential for treating RCC patients with established resistance towards everolimus.

In vitro exposure to very low-level laser modifies expression level of extracellular matrix protein RNAs and mitochondria dynamics in mouse embryonic fibroblasts.

BACKGROUND: Low-level lasers working at 633 or 670 nm and emitting extremely low power densities (Ultra Low Level Lasers - ULLL) exert an overall effect of photobiostimulation on cellular metabolism and energy balance. In previous studies, it was demonstrated that ULLL pulsed emission mode regulates neurite elongation in vitro and exerts protective action against oxidative stress. METHODS: In this study the action of ULLL supplied in both pulsed and continuous mode vs continuous LLL on fibroblast cultures (Mouse Embryonic Fibroblast-MEF) was tested, focusing on mitochondria network and the expression level of mRNA encoding for proteins involved in the cell-matrix adhesion. RESULTS: It was shown that ULLL at 670 nm, at extremely low average power output (0.21 mW/ cm(2)) and dose (4.3 mJ/ cm(2)), when dispensed in pulsed mode (PW), but not in continuous mode (CW) supplied at both at very low (0.21 mW/cm(2)) and low levels (500 mW/cm(2)), modifies mitochondria network dynamics, as well as expression level of mRNA encoding for selective matrix proteins in MEF, e.g. collagen type 1α1 and integrin α5. CONCLUSIONS: We suggest that pulsatility, but not energy density, is crucial in regulating expression level of collagen I and integrin α5 in fibroblasts by ULLL.

Effects of Ganfukang on expression of connective tissue growth factor and focal adhesion kinase/protein kinase B signal pathway in hepatic fibrosis rats.

OBJECTIVE: To investigate the effect of Ganfukang (GFK) on connective tissue growth factor (CTGF) and focal adhesion kinase (FAK)/protein kinase B (PKB or Akt) signal pathway in a hepatic fibrosis rat model and to explore the underlying therapeutic molecular mechanisms of GFK. METHODS: Fifty SD rats were randomly divided into five groups as follows: the control group, the model group (repeated subcutaneous injection of CCl4), and the three GFK treatment groups (31.25, 312.5, and 3125 mg/kg, intragastric administration). Reverse transcriptase-polymerase chain reaction (RT-PCR), Western blotting, and immunohistochemistry were used to examine the expression of CTGF, integrin α5, integrin ß1, FAK/Akt signal pathway, cyclinD1, and collagen in the different-treated rats. RESULTS: GFK attenuated the up-regulation of CTGF, integrin α5, and integrin ß1 in hepatic fibrosis rats and suppressed both the phosphorylation of FAK and the phosphorylation of Akt simultaneously (P<0.01). At the same time, the expression of cyclinD1, collagen I, and collagen III was decreased by GFK significantly (P<0.01). CONCLUSIONS: CTGF and FAK/Akt signal pathway were activated in the CCl4-induced hepatic fibrosis rats, which contribute to increased expression of cyclinD1 and collagen genes. The mechanisms of the anti-fibrosis activity of GFK may be due to its effects against CTGF and FAk/Akt signal pathway.

Antiproliferative and proapoptotic actions of okra pectin on B16F10 melanoma cells.

The proliferation and apoptosis of metastatic melanoma cells are often abnormal. We have evaluated the action of a pectic rhamnogalacturonan obtained by hot buffer extraction of okra pods (okra RG-I) on melanoma cell growth and survival in vitro. We added okra RG-I containing an almost pure RG-I carrying very short galactan side chains to 2D (on tissue culture polystyrene, tPS) and 3D (on poly(2-hydroxyethylmethacrylate), polyHEMA) cultures of highly metastatic B16F10 mouse melanoma cells. We then analyzed cell morphology, proliferation index, apoptosis, cell cycle progression and the expression of adhesion molecules. Immunostaining and western blotting were used to assay galectin-3 (Gal-3) protein.Incubation with okra RG-I altered the morphology of B16F10 cells and significantly reduced their proliferation on both tPS and polyHEMA. The cell cycle was arrested in G2/M, and apoptosis was induced, particularly in cells on polyHEMA. The expression of N-cadherin and alpha5 integrin subunit was reduced and that of the multifunctional carbohydrate-binding protein, Gal-3, at the cell membrane increased.These findings suggest that okra RG-I induces apoptosis in melanoma cells by interacting with Gal-3. As these interactions might open the way to new melanoma therapies, the next step will be to determine just how they occur.