The vacuolar (H+)-ATPases (V-ATPases) are a family of ATP-driven proton pumps and they have been associated with cancer invasion, metastasis, and drug resistance. Despite the clear involvement of V-ATPases in cancer, the therapeutic use of V-ATPase-targeting small molecules has not reached human clinical trials to date. Thus, V-ATPases are emerging as important targets for the identification of potential novel therapeutic agents. We identified a bisbenzimidazole derivative (V) as an initial hit from a similarity search using four known V-ATPase inhibitors (I–IV). Based on the initial hit (V), we designed and synthesized a focused set of novel bisbenzimidazole analogs (2a–e). All newly prepared compounds have been screened for selected human breast cancer (MDA-MB-468, MDA-MB-231, and MCF7) and ovarian cancer (A2780, Cis-A2780, and PA-1) cell lines, along with the normal breast epithelial cell line, MCF10A. The bisbenzimidazole derivative (2e) is active against all cell lines tested. Remarkably, it demonstrated high cytotoxicity against the triple-negative breast cancer (TNBC) cell line, MDA-MB-468 (IC50 = 0.04 ± 0.02 μM). Additionally, it has been shown to inhibit the V-ATPase pump that is mainly responsible for acidification. To the best of our knowledge the bisbenzimidazole pharmacophore has been identified as the first V-ATPase inhibitor in its class. These results strongly suggest that the compound 2e could be further developed as a potential anticancer V-ATPase inhibitor for breast cancer treatment.

Neutrophils kill microorganisms by inducing exocytosis of granules with antibacterial properties. Four isoforms of the "a" subunit of V-ATPase-a1V, a2V, a3V, and a4V-have been identified. a2V is expressed in white blood cells, that is, on the surface of monocytes or activated lymphocytes. Neutrophil associated-a2V was found on membranes of primary (azurophilic) granules and less often on secondary (specific) granules, tertiary (gelatinase granules), and secretory vesicles. However, it was not found on the surface of resting neutrophils. Following stimulation of neutrophils, primary granules containing a2V as well as CD63 translocated to the surface of the cell because of exocytosis. a2V was also found on the cell surface when the neutrophils were incubated in ammonium chloride buffer (pH 7.4) a weak base. The intracellular pH (cytosol) became alkaline within 5 min after stimulation, and the pH increased from 7.2 to 7.8; this pH change correlated with intragranular acidification of the neutrophil granules. Upon translocation and exocytosis, a2V on the membrane of primary granules remained on the cell surface, but myeloperoxidase was secreted. V-ATPase may have a role in the fusion of the granule membrane with the cell surface membrane before exocytosis. These findings suggest that the granule-associated a2V isoform has a role in maintaining a pH gradient within the cell between the cytosol and granules in neutrophils and also in fusion between the surface and the granules before exocytosis. Because a2V is not found on the surface of resting neutrophils, surface a2V may be useful as a biomarker for activated neutrophils.

To evaluate the effect of lameness associated with claw disorders on haemato-biochemical and acute phase protein levels, 34 crossbred dairy cattle were selected from 11 dairy farms. Lame animals were categorized based on locomotion score, hoof lesions and severity of disease. Significant (p LESS THAN 0.05) decrease in Hb, PCV, TEC and lymphocyte count with significant increase in neutrophil count was recorded among animals suffering from various claw disorders. Similar trend was observed in animals showing varying locomotion score, lesions and duration of lameness. Biochemical analysis revealed significant (p LESS THAN 0.05) increase in AST, ALT, TPP and globulin among lame animals. Overall average values of haptoglobin, CRP and fibrinogen among the lame animals were 924.59± 59.13µg/ml, 65.00± 1.98µg/ml and 8.75± 0.51mg/dl compared with 607.02± 49.13µg/ml, 13.79± 0.80µg/ml and 2.78± 0.17mg/dl among healthy animals, respectively. Study concluded that lameness due to claw disorders is associated with a systemic acute phase response as significant (p less than 0.05) increase in levels of fibrinogen, Hp, and CRP was observed.

Screening for couples at risk and prednisone and/or IVIG treatment is an option for women with paternal homozygosity for offending HPA antigen to prevent antenatal sensitization. HPA incompatibility is associated with increased Th1 immunity and NK cell cytotoxicity.

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