Astaxanthin, Compared to Other Carotenoids, Increases the Efficacy of Methotrexate in Rat Adjuvant Arthritis

This in vivo study performed in rat adjuvant arthritis aims to advance the understanding of astaxanthin's therapeutic properties for the possible treatment of rheumatoid arthritis (RA) in monotherapy and along with the standard RA treatment, methotrexate (MTX), in combination therapy. The main goal was to elucidate astaxanthin's full therapeutic potential, evaluate its dose dependency, and compare its effects in monotherapy with other carotenoids such as β-carotene and β-cryptoxanthin (KXAN). Moreover, potential differences in therapeutic activity caused by using different sources of astaxanthin, synthetic (ASYN) versus isolated from Blakeslea trispora (ASTAP), were evaluated using one-way ANOVA (Tukey-Kramer post hoc test). KXAN was the most effective in reducing plasma MMP-9 levels in monotherapy, significantly better than MTX, and in reducing hind paw swelling. The differences in the action of ASTAP and ASYN have been observed across various biometric, anti-inflammatory, and antioxidative parameters. In combined therapy with MTX, the ASYN + MTX combination proved to be better. These findings, especially the significant anti-arthritic effect of KXAN and ASYN + MTX, could be the basis for further preclinical studies.

Anti-Inflammatory Effects of β-Cryptoxanthin on 5-Fluorouracil-Induced Cytokine Expression in Human Oral Mucosal Keratinocytes

Oral mucositis is a typical adverse effect of chemotherapy, causing oral pain that significantly reduces the patient’s quality of life. β-cryptoxanthin (β-cry) is a carotenoid abundant in citrus fruits with antioxidant and anti-inflammatory effects. However, the β-cry effect on oral mucositis remains unclear. We investigated the effects of 5-fluorouracil (5-FU) and β-cry on human normal oral mucosal keratinocytes (hOMK). hOMK was seeded on a culture plate and cultured with 5-FU and β-cry. The cell number, mRNA expression of inflammatory cytokines and matrix metalloproteinases (MMPs), and production of inflammatory cytokines in hOMK were evaluated. Additionally, the cell count and inflammatory cytokine production were analyzed when hOMK was co-stimulated with Porphyromonas gingivalis lipopolysaccharide (P. gingivalis LPS) in addition to 5-FU. The numbers of hOMK significantly reduced with 5-FU stimulation, whereas it increased with β-cry treatment. mRNA expression of interleukin (IL)-6, IL-8, metalloproteinase (MMP)-2, and MMP-9 and protein production of IL-6 and IL-8 in hOMK were augmented on 5-FU stimulation. Simultaneously, β-cry treatment significantly suppressed IL-8 and MMP-9 mRNA expression, and IL-8 production was induced on 5-FU stimulation. Co-stimulation with P. gingivalis LPS and 5-FU enhanced IL-6 and IL-8 production in hOMK. β-cry could enhance cell proliferation and suppress 5-FU-induced expression of inflammatory cytokines and MMP in hOMK. Thus, β-cry can alleviate the symptoms of chemotherapy-induced oral mucositis, and its combination with oral care is effective in managing oral mucositis.

LncRNA PVT1 regulates biological function of osteoarthritis cells by regulating miR-497/AKT3 axis

Growing evidence indicates that lncRNAs are involved in the progression of several diseases, including osteoarthritis (OA). However, the role of the lncRNA PVT1 in OA is still unclear. The present study was aimed at exploring the impact of PVT1 on OA progression, along with potential underlying mechanisms. PVT1 expression levels in articular cartilage tissue of OA patients and non-OA patients were evaluated. To assess the proliferation and apoptosis of chondrocytes subject to treatment, PVT1, miR-497, and AKT3 were either knocked down or upregulated in IL-1β-induced chondrocytes. The variables detected were changes in levels of AKT3 and extracellular matrix (ECM)-related factors (including aggrecan, collagen Type II, and MMP-9). Elevated PVT1 levels were found in cartilage tissue of OA patients and IL-1β-induced chondrocytes. It was also observed that PVT1 knockdown and miR-497 upregulation led to enhanced cell proliferation and suppressed apoptosis. In addition, a decrease in aggrecan and collagen type II levels and an increase in MMP-9 levels were observed in IL-1β-induced chondrocytes. A dual luciferase reporter assay was performed to identify the factors that interacted with miR-497, PVT1, and AKT3. It was observed through rescue experiments that enhancing AKT3 expression or knocking down miR-497 could reverse the impacts of PVT1 knockdown in IL-1β-induced chondrocytes. An upregulation of PVT1 is observed in OA patients. On the other hand, PVT1 knockdown can decrease the effects of IL-1β on the proliferation, apoptosis, and expression of ECM-related proteins of chondrocytes through the regulation of the miR-497/AKT3 axis. PVT1 levels are elevated in the cartilage tissue of OA patients and IL-1β-induced chondrocytes. PVT1 knockdown alleviates the effects of IL-1β treatment on the proliferation and apoptosis of chondrocytes and ECM degradation in chondrocytes by regulating the miR-497/AKT3 axis.

Anti-Inflammatory and Anticancer Effects of Microalgal Carotenoids

Acute inflammation is a key component of the immune system's response to pathogens, toxic agents, or tissue injury, involving the stimulation of defense mechanisms aimed to removing pathogenic factors and restoring tissue homeostasis. However, uncontrolled acute inflammatory response may lead to chronic inflammation, which is involved in the development of many diseases, including cancer. Nowadays, the need to find new potential therapeutic compounds has raised the worldwide scientific interest to study the marine environment. Specifically, microalgae are considered rich sources of bioactive molecules, such as carotenoids, which are natural isoprenoid pigments with important beneficial effects for health due to their biological activities. Carotenoids are essential nutrients for mammals, but they are unable to synthesize them; instead, a dietary intake of these compounds is required. Carotenoids are classified as carotenes (hydrocarbon carotenoids), such as α- and β-carotene, and xanthophylls (oxygenate derivatives) including zeaxanthin, astaxanthin, fucoxanthin, lutein, α- and β-cryptoxanthin, and canthaxanthin. This review summarizes the present up-to-date knowledge of the anti-inflammatory and anticancer activities of microalgal carotenoids both in vitro and in vivo, as well as the latest status of human studies for their potential use in prevention and treatment of inflammatory diseases and cancer.

Pandanus conoideus Lamk Oil Protects Against Inflammation Through Regulating Reactive Oxygen Species in LPS-Induced Murine Macrophages

The aim of this study was to investigate the anti-inflammatory properties of Pandanus conoideus Lamk (red fruit oil [RFO]) and establish the signal pathway of the leading compounds. RAW 264.7 murine macrophage cells were used with lipopolysaccharide (LPS). Cell viability and the pro-inflammatory factors were investigated using MTT assay, real-time polymerase chain reaction (PCR), western blot analysis, and enzyme-linked immunosorbent assay. The quantification of leading compounds in RFO was performed using high-performance liquid chromatography (HPLC). RFO did not reduce RAW 264.7 cell viability. RFO significantly reduced the production of nitric oxide (NO), cyclooxygenase-2, and prostaglandin E2, and both the protein level and mRNA level of inducible NO synthase in LPS-induced macrophages. RFO also regulated the reactive oxygen species (ROS) in LPS-induced macrophages. RFO attenuated the translocation of the nuclear factor κB (NF-κB) p65 subunit, phosphorylation of I-κB, p38, extracellular signal-regulated kinase, and c-Jun N-terminal kinase (JNK) in a dose-dependent manner. HPLC analysis determined that 1 g of RFO had 14.05 ± 0.8 mg of β-cryptoxanthin and 7.4 ± 0.7 mg of β-carotene. In conclusion, RFO provides an anti-inflammatory effect by regulating ROS and NF-κB through mitogen-activated protein kinase due to antioxidant activity.

An Evidence-based Review of Medicinal Plants used in Traditional Persian Medicine for Treatment of Osteoarthritis

Osteoarthritis (OA) is known to be the leading cause of pain and disability in the elderly. The prevalence of this disease in adults over 60 years was 9.6% in men and 18% in women. The therapeutic goals of this disease generally include pain relief with the least side effects, improvement of articular function and improvement of life, in which pharmacological and nonpharmacological treatments are performed in different protocols. Due to the common side effects of pain relievers and complaints after invasive joint surgeries, there is a growing interest in the use of Traditional and Complementary protocols in OA treatment. In this paper, different sources of Traditional Persian Medicine (TPM) were searched to obtain any evidence evaluating any medicinal plants in the management of OA. Over 250 effective medicinal plants for the treatment of OA have been introduced in these sources, and by searching electronic databases including PubMed and Scopus, we have found that of these plants, 39 have direct or indirect evidence in the treatment of this complication by different mechanism of actions such as effect on Body mass index (BMI), obesity and dyslipidemia, anti-inflammatory, anti-nociceptive and antioxidant activity. The most important medicinal plants with direct evidence in the management of OA are Allium sativum, Commiphora mukul, Linum usitatissimum, Matricaria chamomilla, Nigella sativa, Zingiber officinale, and Piper nigrum. Medicinal plants seem to be a valuable source for discovering and identifying new drugs for treatment of OA; however, since most of the studies are preclinical, further clinical trials are required to achieve more conclusive results.

The Function of PPARγ/AMPK/SIRT-1 Pathway in Inflammatory Response of Human Articular Chondrocytes Stimulated by Advanced Glycation End Products

Accumulation of advanced glycation end products (AGEs) in the articular cartilage is a major risk factor for osteoarthritis (OA). To determine the mechanistic basis of AGE action in OA, we treated human articular chondrocytes with AGEs, and found that they not only up-regulated the pro-inflammatory cytokines interleukin (IL)-1β and tumor necrosis factor (TNF)-α, but also inhibited AMP-activated protein kinase (AMPK) phosphorylation and decreased sirtuin 1 (SIRT-1) levels in a concentration- and time-dependent manner. Pioglitazone, a peroxisome proliferator-activated receptor-γ (PPARγ) agonist restored the inhibited AMPK and SIRT-1 by AGEs. Pre-treatment of the cells with the agonists or antagonists of AMPK and SIRT-1 respectively abolished and augmented the inflammatory state induced by AGEs. Furthermore, AMPK agonist also restored the levels of SIRT-1 in the AGE-stimulated chondrocytes. Our findings indicate AGEs induce an inflammatory response in human articular chondrocytes via the PPARγ/AMPK/SIRT-1 pathway, which is therefore a potential target in OA therapy.

Xanthophyll: Health benefits and therapeutic insights

Xanthophylls constitute a major part of carotenoids in nature. They are an oxidized version of carotenoid. Xanthophyll has widely drawn scientists' attentions in terms of its functionality, bioavailability and diversity. An assortment of xanthophyll varieties includes lutein, zeaxanthin, β-cryptoxanthin, capsanthin, astaxanthin, and fucoxanthin. Chemically, lutein and zeaxanthin are dipolar carotenoids with hydroxyl groups at both ends of their molecules that bestow hydrophilic properties to them. Hydrophilic affinity in lutein and zeaxanthin makes better bioavailability in reaction with singlet oxygen in water phase, whereas non-polar carotenoids have shown to have less efficiency in scavenging free radicals. Xanthophylls have been studied for their effects in a wide variety of diseases including neurologic, ophthalmologic, oral, allergic and immune diseases. This review highlights pharmaco-pharmaceutical applications of xanthophylls as well asits drug interactions with beta-carotene. Different types of xanthophylls have been shown to have neuroprotective effects. Fucoxanthin demonstrated potent antiplasmodial activity. Lutein and zeaxanthin prevent the progression of age related macular degeneration. They have also demonstrated promising effects on uveitis, retinitis pigmentosa, scleritis, cataracts, glaucoma, retinal ischemia and choroideremia. Astaxanthin showed to have skin protecting effects against ultraviolet light injury. Astaxanthin have anti-allergic activity against the contact dermatitis especially to treat the patients having adverse reactions induced by steroids. Astaxanthin has been reported to exert beneficial effects in preventing oral lichen planus and early stage cancers. β-cryptoxanthin has been considered a good candidate for prevention of bone loss via osteoblastic bone formation and inhibiting osteoclastic bone resorption. There is also some concern that higher dose of xanthophylls may be linked to increased risk of skin cancer and gastric adenocarcinoma. However this increased risk was not statistically significant when adjusted for confounding factors. Further researches including clinical studies are needed to better evaluate the efficacy and safety of xanthophylls in prevention and treatment of different diseases.

Beta-Cryptoxanthin Inhibits Lipopolysaccharide-Induced Osteoclast Differentiation and Bone Resorption via the Suppression of Inhibitor of NF-κB Kinase Activity

Beta-cryptoxanthin (β-cry) is a typical carotenoid found abundantly in fruit and vegetables such as the Japanese mandarin orange, persimmon, papaya, paprika, and carrot, and exerts various biological activities (e.g., antioxidant effects). We previously reported that β-cry suppressed lipopolysaccharide (LPS)-induced osteoclast differentiation via the inhibition of prostaglandin (PG) E₂ production in gingival fibroblasts and restored the alveolar bone loss in a mouse model for periodontitis in vivo. In this study, we investigated the molecular mechanism underlying the inhibitory effects of β-cry on osteoclast differentiation. In mouse calvarial organ cultures, LPS-induced bone resorption was suppressed by β-cry. In osteoblasts, β-cry inhibited PGE₂ production via the downregulation of the LPS-induced mRNA expression of cyclooxygenase (COX)-2 and membrane-bound PGE synthase (mPGES)-1, which are PGE synthesis-related enzymes, leading to the suppression of receptor activator of NF-κB ligand (RANKL) mRNA transcriptional activation. In an in vitro assay, β-cry directly suppressed the activity of the inhibitor of NF-κB kinase (IKK) β, and adding ATP canceled this IKKβ inhibition. Molecular docking simulation further suggested that β-cry binds to the ATP-binding pocket of IKKβ. In Raw264.7 cells, β-cry suppressed RANKL-mediated osteoclastogenesis. The molecular mechanism underlying the involvement of β-cry in LPS-induced bone resorption may involve the ATP-competing inhibition of IKK activity, resulting in the suppression of NF-κB signaling.

Serum Nutrient Levels and Aging Effects on Periodontitis

Periodontal disease damages tissues as a result of dysregulated host responses against the chronic bacterial biofilm insult and approximately 50% of US adults >30 years old exhibit periodontitis. The association of five blood nutrients and periodontitis were evaluated due to our previous findings regarding a potential protective effect for these nutrients in periodontal disease derived from the US population sampled as part of the National Health and Nutrition Examination Survey (1999⁻2004). Data from over 15,000 subjects was analyzed for blood levels of cis-β-carotene, β-cryptoxanthin, folate, vitamin D, and vitamin E, linked with analysis of the presence and severity of periodontitis. Moderate/severe disease patients had lower cis-β-carotene levels across all racial/ethnic groups and these decreased levels in moderate/severe periodontitis were exacerbated with age. β-cryptoxanthin demonstrated lower levels in severe disease patients across the entire age range in all racial/ethnic groups. Folate differences were evident across the various age groups with consistently lower levels in periodontitis patients >30 years and most pronounced in females. Lower levels of vitamin D were consistently noted across the entire age range of patients with a greater difference seen in females with periodontitis. Finally, an analytical approach to identify interactions among these nutrients related to age and periodontitis showed interactions of vitamin D in females, and folate with race in the population. These findings suggest that improving specific nutrient intake leading to elevated blood levels of a combination of these protective factors may provide a novel strategy to affect the significant increase in periodontitis that occurs with aging.

CTX-II and YKL-40 in early diagnosis and treatment evaluation of osteoarthritis

This study investigated the value of C-terminal telopeptides of collagen type II (CTX-II) and YKL-40 in early diagnosis and treatment evaluation of osteoarthritis (OA). A total of 90 patients with OA diagnosed and treated in The First Affiliated Hospital, Guangzhou Medical University from March 2015 to January 2018 were selected as the study group. At the same time, 50 healthy elderly were included as the control group. The study group was divided into three subgroups including group A (29 cases, 500 mg glucosamine sulfate), group B (29 cases, 50 mg diacerein) and group C (32 cases, 500 mg glucosamine sulfate and 50 mg diacerein). Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) was used to assess the severity and treatment of arthritis. Enzyme-linked immunosorbent assay was used to measure the concentration of CTX-II and YKL-40 in serum. WOMAC scores in the study A, B and C groups were significantly higher than those in the control group (P<0.001). Serum CTX-II and YKL-40 concentrations were higher in the study group than in the control group (P<0.001). Sensitivity of serum CTX-II combined with YKL-40 in the diagnosis of OA was 90% and the specificity was 78%. CTX-II and YKL-40 levels in different Kellgren Lawrence (K-L) grades were significantly different (P<0.001), and increased with the increase of K-L grade. Concentrations of serum CTX-II and YKL-40 before treatment in the study group was positively correlated with WOMAC score (P<0.001). At 3, 6 and 9 weeks after the beginning of treatment, serum concentrations of CTX-II and YKL-40 decreased significantly (P<0.001). At 3 weeks of treatment, CTX-II was positively correlated with YKL-40 concentration and WOMAC score (r=0.406, P<0.001; r=0.430, P<0.001); CTX-II was positively correlated with YKL-40 concentration and WOMAC score at 6 weeks of treatment (r=0.350, P<0.001; r=0.358, P<0.001); CTX-II was positively correlated with YKL-40 concentration and WOMAC score at 9 weeks after treatment (r=0.370, P<0.001; r=0.394, P<0.001). Combined detection of serum CTX-II and YKL-40 can improve the sensitivity of early OA diagnosis, and it has an important diagnostic value for early OA patients. Therefore, it can be used as a biological indicator for early OA diagnosis, severity assessment, and evaluation of treatment effects.