Gingiva-derived Stromal Cells Isolated from Cats Affected with Tooth Resorption Exhibit Increased Apoptosis, Inflammation, and Oxidative Stress while Experiencing Deteriorated Expansion and Anti-Oxidative Defense.

Gingiva-derived mesenchymal stromal cells (GMSCs) are multipotent cells characterized by multilineage differentiation potential, proliferative expansion, and unique immunomodulatory ability, making them attractive as a new treatment of periodontal regeneration. In this study, GMSCs obtained from the gingiva of healthy cats (HE) as well as from cats affected by tooth resorption (TR) were isolated and characterized. Feline GMSCs (fGMSCs) from HE patients exhibited fibroblast-like morphology, developed cellular body, specific growth pattern, high expansion, and proliferative potential as well as reduced senescence signature. fGMSCs demonstrated high s-100 and IL-10 positive cells, while simultaneously having low activity of IL-1. Moreover, high activity of ki-67 combined with reduced senescence markers were noted. In comparison, GMSCs from cats with TR exhibited enlarged nuclei and flat, irregular shape along with increased expression of CD44, s-100 and CD45 and downregulation of CD73. GMSCs from TR cats showed lower ability to form colonies, increased incidence of apoptosis, higher number of senescent cells, and reduced cell migration. Upregulation of pro-inflammatory cytokines was also noted in the TR group along with lower expression of mTOR and miR-17 and upregulation of miR-378. Mitochondrial dynamics, biogenesis and antioxidant properties are also negatively impacted in this group. Collectively, our findings suggest that GMSCs isolated from the gingiva of cats affected with TR have deteriorated functionality caused by impaired proliferation and growth and possibly mediated via mitochondrial dysfunction. fGMSCs or their EV's should be further investigated for their role in the pathophysiology of TR in cats.

Tetrahydrocannabivarin (THCV) Protects Adipose-Derived Mesenchymal Stem Cells (ASC) against Endoplasmic Reticulum Stress Development and Reduces Inflammation during Adipogenesis.

The endoplasmic reticulum (ER) fulfills essential duties in cell physiology, and impairment of this organelle's functions is associated with a wide number of metabolic diseases. When ER stress is generated in the adipose tissue, it is observed that the metabolism and energy homeostasis of the adipocytes are altered, leading to obesity-associated metabolic disorders such as type 2 diabetes (T2D). In the present work, we aimed to evaluate the protective effects of Δ9-tetrahydrocannabivarin (THCV, a cannabinoid compound isolated from Cannabis sativa L.) against ER stress in adipose-derived mesenchymal stem cells. Our results show that pre-treatment with THCV prevents the subcellular alteration of cell components such as nuclei, F-actin, or mitochondria distribution, and restores cell migration, cell proliferation and colony-forming capacity upon ER stress. In addition, THCV partially reverts the effects that ER stress induces regarding the activation of apoptosis and the altered anti- and pro-inflammatory cytokine profile. This indicates the protective characteristics of this cannabinoid compound in the adipose tissue. Most importantly, our data demonstrate that THCV decreases the expression of genes involved in the unfolded protein response (UPR) pathway, which were upregulated upon induction of ER stress. Altogether, our study shows that the cannabinoid THCV is a promising compound that counters the harmful effects triggered by ER stress in the adipose tissue. This work paves the way for the development of new therapeutic means based on THCV and its regenerative properties to create a favorable environment for the development of healthy mature adipocyte tissue and to reduce the incidence and clinical outcome of metabolic diseases such as diabetes.

Studies on the Anticancer and Antioxidant Activities of Resveratrol and Long-Chain Fatty Acid Esters.

Resveratrol (RES) is gaining recognition as a natural bioactive compound. To expand the possible applications of RES with its enhanced bioactivity as well as to increase the health benefits of long-chain fatty acids, a lipophilization process of RES was performed using three fatty acids: palmitic acid (PA), oleic acid (OA), and conjugated linoleic acid (CLA). The obtained mono-, di-, and tri-esters of RES were evaluated for their anticancer and antioxidant properties against lung carcinoma (A549), colorectal adenocarcinoma (HT29), and pancreatic ductal adenocarcinoma (BxPC3) cell lines. Human fibroblast (BJ) cells were used as a control. Several parameters were investigated: cell viability and apoptosis, including the expression of major pro- and anti-apoptotic markers, as well as the expression of superoxide dismutase, a key enzyme of the body's antioxidant barrier. Three of the obtained esters: mono-RES-OA, mono-RES-CLA, and tri-RES-PA, which significantly reduced the tumor cell viability up to 23%, at concentrations 25, 10, 50 µg/mL, respectively, turned out to be particularly interesting. The above-mentioned resveratrol derivatives similarly increased the tumor cells' apoptosis by modifying their caspase activity of pro-apoptotic pathways (p21, p53, and Bax). Moreover, among the mentioned esters, mono-RES-OA induced apoptosis of the analyzed cell lines most strongly, reducing the number of viable cells up to 48% for HT29 cells versus 36% for pure RES. Furthermore, the selected esters exhibited antioxidant properties towards the normal BJ cell line by regulating the expression of major pro-antioxidant genes (superoxide dismutases-SOD1 and SOD2) without the effect on their expression in the tumor, and therefore reducing the defense of cancer cells against increased oxidative stress induced by high ROS accumulation. The obtained results indicate that the esters of RES and long-chain fatty acids allow enhancement of their biological activity. The RES derivatives have the potential for being applied in cancer prevention and treatment, as well as for oxidative stress suppression.

Cannabidiol (CBD) Protects Adipose-Derived Mesenchymal Stem Cells (ASCs) against Endoplasmic Reticulum Stress Development and Its Complications.

BACKGROUND: Recent studies suggested that individuals with metabolic disorders have altered function of adipocytes and adipose stem cell subpopulations, which impairs tissue homeostasis, promoting insulin resistance and diabetes development. The non-psychoactive phytocannabinoid CBD was found to modulate adipose tissue metabolism, however, its exact role in controlling ASCs' fate is still poorly understood. OBJECTIVES: This investigation aimed to elucidate whether pretreatment of ASCs with CBD can protect against ER stress development and maintain the cytophysiological properties of cells. METHODS: Human ASCs were cultured under control and adipogenic conditions. Prior to the experiments, cells in the experimental group were pretreated with CBD following the addition of an ER stress inducer-tunicamycin. After the experiments, the cells were subsequently tested for expression of the apoptotic, ER stress, and anti-inflammatory-related genes using RT-qPCR. Oxidative stress was analysed with flow cytometric assays. RESULTS: Cells pretreated with CBD displayed decreased apoptosis and enhanced proliferation rate. Additionally, the expression of pro-inflammatory cytokines and miRNAs was significantly reduced. The obtained results also demonstrated an obvious reduction in intracellular accumulated ROS and NO, as well as mitigated ER stress through the down-regulation of IRE-1, PERK, CHOP, and ATF6 transcripts upon CBD treatment. CONCLUSION: The presented data provide the evidence that CBD protects ASCs against ER stress development and its complications and, thus, offers new insights for the management of obesity through the regulation of adipose tissue dynamics.