Knee osteoarthritis (KOA), one of the most common orthopedic disorders concerning the adult population worldwide, is a condition characterized by progressive destruction of the articular cartilage and the presence of an inflammatory process. The aim of our study was to assess whether nicotinamide riboside (NR), a popular anti-aging supplement, can reduce the rate of cartilage destruction and alleviate the inflammatory response compared to the commonly prescribed collagen supplement in a murine monoiodoacetate (MIA)-induced KOA model. Twenty Wistar rats were randomly assigned to 4 groups: sham (S), MIA and NR, MIA and hydrolyzed collagen (HC), and MIA. At the end of the experiment, the right knees and blood samples were collected for histological assessment and biochemical evaluation of nitric oxide, malondialdehyde, total antioxidant capacity, reduced glutathione, glutathione peroxidase, superoxide dismutase, catalase, myeloperoxidase, and tumoral necrosis factor-alpha (TNF-α). The study determined that the treatment with NR in a similar dose with HC decreased blood/serum levels of oxidative stress biomarkers and the histological lesions in almost the same manner. The present findings suggest that NR may exhibit chondroprotective and anti-inflammatory effects in MIA-induced KOA in rats.

Iron oxide nanoparticles (IONPs) represent an important advance in the field of medicine with application in both diagnostic and drug delivery domains, offering a therapeutic approach that effectively overcomes physical and biological barriers. The current study aimed to assess whether oral administration of salicylic acid-functionalized iron oxide nanoparticles (SaIONPs) may exhibit beneficial effects in alleviating histological lesions in a murine monoiodoacetate (MIA) induced knee osteoarthritis model. In order to conduct our study, 15 Wistar male rats were randomly distributed into 3 work groups: Sham (S), MIA, and NP. At the end of the experiments, all animals were sacrificed for blood, knee, and liver sampling. Our results have shown that SaIONPs reached the targeted sites and also had a chondroprotective effect represented by less severe histological lesions regarding cellularity, altered structure morphology, and proteoglycan depletion across different layers of the knee joint cartilage tissue. Moreover, SaIONPs induced a decrease in malondialdehyde (MDA) and circulating Tumor Necrosis Factor-α (TNF-α) levels. The findings of this study suggest the therapeutic potential of SaIONPs knee osteoarthritis treatment; further studies are needed to establish a correlation between the administrated dose of SaIONPs and the improvement of the morphological and biochemical parameters.

Knee osteoarthritis (OA) is a complex, progressive disorder that involves the gradual breakdown of articular cartilage, alteration of the subchondral bone, synovial inflammation, and joint space limitation, ultimately leading to stiffness, pain, and impaired balance and mobility. At this moment there is no cure to stop the evolution of the disease, only symptomatic treatment. This fact is due to the lack of understanding of the underlying mechanisms, thus limiting the possibilities of developing disease-modifying drugs. This challenge arises from an incomplete understanding of the underlying mechanisms of disease, which limits the development of effective disease-modifying drugs due to the fact that human tissue samples are typically obtained in the advanced stages of the disease, usually when the patient is subjected to joint replacement surgery, making the study of early OA stages more difficult. For researchers, the murine animal model provides a useful tool for assessing the full evolution of the pathology and the study of the efficacy and safety of novel experimental drugs and supplements. The aim of our review is to present the diverse currently used murine models ranging from spontaneous to chemically and surgically induced OA and pharmacological results that were obtained on such models and are available for human use or represent a potential innovative therapy in the near future.

Connections between vitamin D and psoriasis have been a matter of interest for the past decades, with its active metabolite, 1,25(OH)₂ vitamin D, being valued for antiproliferative and immunomodulatory effects. However, none of vitamin D’s actions could be possible without the CYP27B1 enzyme that bio-activates this metabolite of interest. In order to see if there is any link between the enzyme expression and the disease’s particularities, we conducted a preliminary study that involved 11 skin biopsies of patients with mild (n = 4) or moderate to severe psoriasis (n = 7). The cell proliferation antigen Ki67 and the CD45RO+ marker were also assessed. Compared with healthy skin, in psoriasis, it is reported that the enzyme’s expression seems to be more ubiquitous, but a clear correlation between the disease’s severity and the CYP27B1 expression was, to our knowledge, lacking. We found that, in patients with very mild psoriasis, the enzyme expression was observed in the epidermal stratum basale in a similar manner as in healthy skin specimens. Contrary, for higher severity scores, a divergent result was observed, with the enzyme being either variably spread in the epidermal stratum spinosum or completely absent. Unlike malignant diseases, a significant connection between CYP27B1 and Ki67 (p = 0.313) or CYP27B1 and CD45RO+ (p = 0.657) does not seem to be relevant in psoriasis.

Suboptimal states of vitamin D may play a role in psoriasis evolution, but the interconnections have been studied over the past years with controversial results. Although a peerless therapy among moderate to severe types of psoriasis, the therapeutic effectiveness of biological therapy may vary unforeseeably between patients and leads to biologics switch. We conducted a pilot study in patients diagnosed with psoriasis and treated with biologics, the purpose of which was to explore the prevalence of suboptimal states of vitamin D, especially in the group of patients characterized by the failure of previous biologics, and to investigate the associations between vitamin D levels and psoriasis, regarding aspects such the severity of the disease and quality of life. Their current result of latent tuberculosis infection (LTBI) was also considered concerning a feasible relationship with vitamin D levels. From July to December 2021, 45 patients corresponding to our inclusion criteria were assessed. Variables such as Psoriasis Area and Severity Index (PASI) score and the Dermatology Life Quality Index (DLQI) score, as well as vitamin D serum concentrations and their LTBI result, were recorded for them. Lower serum concentrations of vitamin D were not more common in patients characterized by failure to previous biologics (p = 0.443), but we concluded a weak correlation between the DLQI score and vitamin D (rho = −0.345, p-value = 0.020), although a statistically insignificant result was obtained between vitamin D and the PASI score (rho = −0.280, p-value = 0.062), and with the LTBI result (rho = −0.053, p-value = 0.728). These results establish a connection between higher levels of vitamin D and a better outcome of psoriasis from the perspective of the patient’s quality of life, with no significant association with psoriasis severity and no significant prevalence of suboptimal states among patients that failed previous biologics compared to those with a continuously good response.

Green tea supplements (GTSs) are a favorite among the general population and, due to their methylxanthine (caffeine, theobromine, theophylline) content, might represent a potential ergogenic source in athletes’ performance. The aim of this study was to develop and validate a method that quantifies the methylxanthine content of commercially available GTSs and to evaluate their potential relevance for ergogenic use. An ultra-high-performance liquid chromatography coupled with photodiode array detection and a QDa mass detector (UHPLC–PDA–QDa) method was developed, validated and applied to determine the content of methylxanthines in seven commercially available GTSs. Method validation parameters demonstrated satisfactory performance, with rapid and efficient separation and quantification of the three methylxanthines. Considerable variability was observed among the analyzed products, with caffeine, theobromine, and theophylline contents ranging from 0.37 to 12.13, 0.07 to 3.59, and 0.05 to 0.83 mg/capsule, respectively. However, the methylxanthine amounts measured in the analyzed products were below the doses commonly associated with ergogenic effects. Overall, the developed UHPLC–PDA–QDa method provided a reliable approach for methylxanthine quantification, while the seven products analyzed did not represent meaningful ergogenic sources of these compounds.