Physical interaction of CCN2 with diverse growth factors involved in chondrocyte differentiation during endochondral ossification

CCN family member 2 (CCN2) has been shown to promote the proliferation and differentiation of chondrocytes, osteoblasts, osteoclasts, and vascular endothelial cells. In addition, a number of growth factors and cytokines are known to work in harmony to promote the process of chondrogenesis and chondrocyte differentiation toward endochondral ossification. Earlier we showed that CCN2 physically interacts with some of them, suggesting that multiple effects of CCN2 on various differentiation stages of chondrocytes may be attributed to its interaction with these growth factors and cytokines. However, little is known about the functional interaction occurring between CCN2 and other growth factors and cytokines in promoting chondrocyte proliferation and differentiation. In this study we sought to shed light on the binding affinities between CCN2 and other essential growth factors and cytokines known to be regulators of chondrocyte differentiation. Using the surface plasmon resonance assay, we analyzed the dissociation constant between CCN2 and each of the following: TGF-β1, TGF-β3, IGF-I, IGF-II, PDGF-BB, GDF5, PTHrP, and VEGF. We found a strong association between CCN2 and VEGF, as well as a relatively high association with TGF-β1, TGF-β3, PDGF-BB, and GDF-5. However, the sensorgrams obtained for possible interaction between CCN2 and IGF-I, IGF-II or PTHrP showed no response. This study underlines the correlation between CCN2 and certain other growth factors and cytokines and suggests the possible participation of such interaction in the process of chondrogenesis and chondrocyte differentiation toward endochondral ossification.     

Diversity,phytochemical and medicinal potential of the genus Ocimum L. (Lamiaceae)

Phytochemistry Reviews - Ocimum, commonly known as Tulsi, is a huge genus within family Lamiaceae, comprising about 64 species of annual to perennial aromatic medicinal herbs with a long history of...     

Applicability of fluorescamine as a fluorogenic reagent for highly sensitive fluorimetric analysis of the tyrosine kinase inhibitor (avapritinib) in pharmaceuticals and biological samples

Avapritinib (AVP) was the first precision drug to be approved by the US Food and Drug Administration (FDA) in 2020 for patients suffering from metastatic gastrointestinal stromal tumors (GISTs) and progressive systemic mastocytosis. The analysis of AVP in pharmaceutical tablets and human plasma was then carried out using a fast, efficient, sensitive, and simple fluorimetric method using a fluorescamine reagent. The procedure is based on the interaction between fluorescamine as a fluorogenic reagent and the primary aliphatic amine moiety in AVP using borate buffer solution at pH 8.8. The produced fluorescence was measured at 465 nm (Excitation at 395 nm). The calibration graph's linearity range was discovered to be 45.00–500.0 ng mL⁻¹. Utilizing the International Council for Harmonization (ICH) and US-FDA recommendations, the research technique was validated and bioanalytically validated. The proposed approach was effectively employed for determining the stated pharmaceuticals in plasma with a high percentage of recovery ranging from 96.87 to 98.09 and pharmaceutical formulations with a percentage of recovery equal to 102.11% ± 1.05%. In addition, the study was extended to a pharmacokinetic study of AVP with 20 human volunteers as a step for AVP management in therapeutic cancer centers.     

Moult strategies of Cory’s Shearwaters Calonectris diomedea borealis: the influence of colony location, sex and individual breeding status

The replacement of old feathers is essential for birds, but it is also an energy-demanding task. As moult usually does not coincide with other stressful events in its annual cycle, such as reproduction and migration, the bird can optimise its use of time and energy allocated to different activities. There are very few studies comparing the moult strategies of populations with similar breeding calendars but occurring in areas of different habitat quality. Cory’s Shearwaters Calonectris diomedea have a partial moult–breeding overlap, an unusual phenomenon among pelagic seabirds. We have compared the moult schedules in Cory’s Shearwater colonies located in distinct environments (pelagic vs. coastal) and show that moult–breeding overlap is less extensive on Selvagem Grande, situated in deep oceanic waters, than on Berlenga, situated on the continental shelf. Colony attendance of failed breeders, most of which were moulting, was lower at Selvagem Grande than at Berlenga, which suggests that the feeding areas of birds from the former site are more distant from the colony. Failed breeders started to moult earlier than individuals still raising a chick, and breeding status had a stronger influence on determining the onset of wing-feather moult than colony location. Despite published evidence that internal circannual rhythms and external cues, such as variation in daylength, are important factors regulating moult schedules, it is clear that birds retain a considerable flexibility that allows them to respond to external factors in order to strategically manage time and energy in a way that is thought to maximise their fitness.     

Salivary exosomes as a new therapy to ameliorate diabetes mellitus and combat xerostomia and submandibular salivary glands dysfunction in diabetic rats

Journal of Molecular Histology - Diabetes mellitus (DM) is one of the major metabolic diseases. Xerostomia and salivary gland dysfunction are of its common oral complications. Exosomes, as a new...