Oral preparation of hyaluronic acid, chondroitin sulfate, N-acetylglucosamine, and vitamin C improves sexual and urinary symptoms in participants with recurrent urinary tract infections: a randomized crossover trial.

BACKGROUND: Intravesical instillation of hyaluronic acid (HA) has been associated with reduced sexual dysfunction in participants with recurrent urinary tract infections (rUTIs), but the efficacy of an oral treatment has never been investigated. AIM: To investigate the efficacy of an oral preparation of HA, chondroitin sulfate, N-acetylglucosamine, and vitamin C in improving sexual and urinary symptoms in a cohort of reproductive-age participants with rUTI. METHODS: In a monocentric randomized crossover pilot trial, participants with rUTI who were referred to our institute between March 2022 and April 2023 were randomized 1:1 in 2 groups: intervention vs control. All participants had an oral preparation of cranberry, D-mannose, propolis extract, turmeric, and Boswellia twice a day for 3 months. The intervention group also included an oral preparation of HA, chondroitin sulfate, N-acetylglucosamine, and vitamin C once a day for 3 months. Crossover of treatment occurred at 3 months for an additional 3 months. At baseline and 3 and 6 months, participants were evaluated clinically and with the International Prostate Symptom Score (IPSS) and Female Sexual Function Index (FSFI). Descriptive statistics and logistic regression models tested the impact of the intervention on urinary and sexual symptoms at each follow-up assessment. OUTCOMES: Improvement in sexual and urinary symptoms as measured by the FSFI and IPSS. RESULTS: Overall, 27 (54%) participants had an FSFI score <26.5 at enrollment. At 3 months, FSFI scores were higher in the intervention group vs control (P < .001), but IPSS scores were lower (P = .03). After crossover of treatment, FSFI and IPSS scores remained stable in the intervention group. However, after crossover, the control group showed a significant improvement in IPSS and FSFI scores (all P < .01) vs the 3-month assessment. At last follow-up, urinary and sexual symptoms were comparable between groups. In logistic regression analyses, the intervention group was associated with early improvement in sexual symptoms (odds ratio, 3.9; P = .04) and urinary symptoms (odds ratio, 5.1; P = .01) after accounting for clinical confounders. CLINICAL IMPLICATIONS: Combination treatment with HA, chondroitin sulfate, N-acetylglucosamine, and vitamin C is effective if started immediately or even after a few months from symptoms in participants with rUTI. STRENGTHS AND LIMITATIONS: The main limitation is the lack of long-term follow-up. CONCLUSION: The oral formulation of HA, chondroitin sulfate, N-acetylglucosamine, and vitamin C could be an effective therapy against urinary and sexual distress in participants with rUTI (NCT06268483; ClinicalTrials.gov).

N-acetylglucosamine drives myelination by triggering oligodendrocyte precursor cell differentiation.

Myelination plays an important role in cognitive development and in demyelinating diseases like multiple sclerosis (MS), where failure of remyelination promotes permanent neuro-axonal damage. Modification of cell surface receptors with branched N-glycans coordinates cell growth and differentiation by controlling glycoprotein clustering, signaling, and endocytosis. GlcNAc is a rate-limiting metabolite for N-glycan branching. Here we report that GlcNAc and N-glycan branching trigger oligodendrogenesis from precursor cells by inhibiting platelet-derived growth factor receptor-α cell endocytosis. Supplying oral GlcNAc to lactating mice drives primary myelination in newborn pups via secretion in breast milk, whereas genetically blocking N-glycan branching markedly inhibits primary myelination. In adult mice with toxin (cuprizone)-induced demyelination, oral GlcNAc prevents neuro-axonal damage by driving myelin repair. In MS patients, endogenous serum GlcNAc levels inversely correlated with imaging measures of demyelination and microstructural damage. Our data identify N-glycan branching and GlcNAc as critical regulators of primary myelination and myelin repair and suggest that oral GlcNAc may be neuroprotective in demyelinating diseases like MS.

MicroSPECT Imaging-Guided Treatment of Idiopathic Pulmonary Fibrosis in Mice with a Vimentin-Targeting 99mTc-Labeled N-Acetylglucosamine-Polyethyleneimine.

Idiopathic pulmonary fibrosis (IPF) is a progressive fibrotic disease with poor prognosis. Evidence has shown that vimentin is a key regulator of lung fibrogenesis. 99mTc-labeled N-acetylglucosamine-polyethyleneimine (NAG-PEI), a vimentin-targeting radiotracer, was used for the early diagnosis of IPF, and NAG-PEI was also used as a therapeutic small interfering RNA (siRNA) delivery vector for the treatment of IPF in this study. Single-photon emission-computed tomography (SPECT) imaging of bleomycin (BM)- and silica-induced IPF mice with 99mTc-labeled NAG-PEI was performed to visualize pulmonary fibrosis and monitor the treatment efficiency of siRNA-loaded NAG-PEI, lipopolysaccharide (LPS, a tolerogenic adjuvant), or zymosan (ZYM, an immunostimulant). The lung uptakes of 99mTc-NAG-PEI in the BM- and silica-induced IPF mice were clearly and directly correlated with IPF progression. The lung uptake of 99mTc-NAG-PEI in the NAG-PEI/TGF-ß1-siRNA treatment group or LPS treatment group was evidently lower than that in the control group, while the lung uptake of 99mTc-NAG-PEI was significantly higher in the ZYM treatment group compared to that in the control group. These results demonstrate that NAG-PEI is a potent MicroSPECT imaging-guided theranostic platform for IPF diagnosis and therapy.

N-Acetylglucosamine is the most effective glucosamine derivative for the treatment of membranous nephropathy in rats.

Nephroprotective drug development for optimizing treatment of chronic kidney disease (CKD) is an important task of pharmaceutical science. Our study evaluated nephroprotective properties of the two glucosamine derivatives N-acetylglucosamine and glucosamine hydrochloride in a 3-week-long parenteral and oral daily administration at doses of 50 mg/kg in rats with doxorubicin nephropathy. Nephroprotective activity (NA) was evaluated by determining the functional state of the kidneys, the level of azotemia and the activity of free-radical processes in the renal tissue. The results show a significant increase in renal excretory function, normalization of nitrogen metabolism and a decline of free-radical processes under the influence of both studied amino sugars in rats with doxorubicin nephropathy. I. m. route of administration yielded the highest efficacy for both amino sugars with the highest level of NA (83.3%) shown by N-acetylglucosamine. Thus N-acetylglucosamine in i. m. injections has the highest NA among the glucosamine derivatives, and is a promising agent for CKD treatment.

Dietary Natural N-Acetyl-d-Glucosamine Prevents Bone Loss in Ovariectomized Rat Model of Postmenopausal Osteoporosis.

Postmenopausal osteoporosis has seriously affected the life quality of elderly women. A natural polymer, chitin, obtained from shells of crab and shrimp, has been widely used in the biomedical field owing to its nontoxicity, biocompatibility, and biodegradability. In this study, natural N-acetyl-d-glucosamine (NAG) was prepared from liquefied chitin. The protective activities of NAG in postmenopausal osteoporosis were evaluated on Sprague Dawley rats and osteoblast-based models. Results showed that oral administration of NAG boosted trabecular bone volume and trabecular numbers. Additionally, the calcium content in the femur and tibia increased, and femoral biomechanical properties improved. Furthermore, NAG supplementation significantly lowered alkaline phosphatase levels and increased calcium content in the serum of ovariectomized rats. In vitro studies showed that NAG markedly promoted cell proliferation and stimulated osteoblast differentiation of mouse calvaria origin MC3T3-E1 cells with increased alkaline phosphatase activity in a concentration-dependent manner. Moreover, NAG effectively protected osteoblasts from oxidative damage induced by hydrogen peroxide. In conclusion, our data provide an additional foundation for dietary supplementation of NAG, which could protect and reverse osteopenia in postmenopausal women.

PUGNAc treatment provokes globotetraosylceramide accumulation in human umbilical vein endothelial cells.

PUGNAc is a well-investigated inhibitor for protein-O-GlcNAcase, whereas recent investigations showed that PUGNAc had a broad range as inhibitor for cellular ß-hexosaminidases. Here we report that PUGNAc treatment provokes globotetraosylceramide (Gb4Cer) accumulation in human umbilical vein endothelial cells (HUVEC). HPLC analysis and a quantitative ELISA using newly developed anti-Gb4Cer monoclonal antibody revealed that PUGNAc treatment specifically increased the expression of Gb4Cer among glycosphingolipids expressed in HUVEC. Although the effect was weaker than PUGNAc, an O-GlcNAcase selective inhibitor (Thiamet-G) treatment also increased Gb4Cer levels in HUVEC. Furthermore, both of PUGNAc and Thiamet-G treatment up-regulated the expression levels of α-1,4-galactosyltransferase/Gb3Cer synthase gene which encodes a key enzyme in Gb4Cer synthesis. These results indicate that protein-O-GlcNAcylation can regulate the expression levels of cellular Gb4Cer.

In Vivo Anticancer Efficacy and Toxicity Studies of a Novel Polymer Conjugate N-Acetyl Glucosamine (NAG)-PEG-Doxorubicin for Targeted Cancer Therapy.

A novel polymer-drug conjugate, polyethylene glycol-N-(acetyl)-glucosamine-doxorubicin (PEG-NAG-DOX) was evaluated in this study for its in vivo potential for treatment of tumours demonstrating improved efficacy and reduced toxicity. The proposed polymer-drug conjugate comprised of polyethylene glycol-maleimide (mPEG-MAL, 30000 Da) as a carrier, doxorubicin (DOX) as an anticancer drug and N-acetyl glucosamine (NAG) as a targeting moiety as well as penetration enhancer. Doxorubicin has a potent and promising anticancer activity; however, severe cardiotoxicity limits its application in cancer treatment. By modifying DOX in PEG-NAG-DOX prodrug conjugate, we aimed to eliminate this limitation. In vivo anticancer efficacy of the conjugate was evaluated using BDF mice-induced skin melanoma model by i.v. administration of DOX conjugates. Anticancer efficacy studies were done by comparing tumour volume, body weight, organ index and percent survival rate of the animals. Tumour suppression achieved by PEG-NAG-DOX at the cumulative dose of 7.5 mg/kg was two-fold better than that achieved by DOX solution. Also, the survival rate for PEG-NAG-DOX conjugate was >70% as compared to <50% survival rate for DOX solution. In addition, toxicity studies and histopathological studies revealed that while maintaining its cytotoxicity towards tumour cells, PEG-NAG-DOX conjugate showed no toxicities to major organs. Therefore, PEG-NAG-DOX conjugate can be suggested as a desirable candidate for targeted cancer therapy.

A Firming Neck Cream Containing N-Acetyl Glucosamine Significantly Improves Signs of Aging on the Challenging Neck and Décolletage.

BACKGROUND: Noninvasive antiaging neck and décolletage treatments are highly sought after by aging patients. A topical cosmetic antiaging cream was formulated with skin matrix building and smoothing ingredients to help reverse visible signs of aging on the neck and décolletage, including laxity, crepiness, deep lines, and hyperpigmentation. OBJECTIVE: A clinical study was conducted to evaluate the efficacy and safety of the antiaging neck/décolletage cream over a 16-week treatment period. METHOD: Caucasian women with moderate texture (including wrinkles, fine lines, laxity, and/or crepiness) on the neck and hyperpigmentation on the décolletage used the test cream for 16 weeks. At weeks 0, 8, 12 and 16, the dermatologist investigator graded neck texture, décolletage texture and décolletage pigmentation using a 0-5 scale, and irritation/tolerability using a 0-4 scale. Subjects were photographed and provided self-assessment of their aging parameters as well as product tolerability. Chromameter measurements were collected in triplicate on the chest at weeks 0, 8, and 16 to quantitatively and objectively assess pigmentation. RESULTS: Forty-two women completed the study. All dermatologist-graded aging parameters were significantly improved at each time point, P<0.001. Chromameter measurements demonstrated significant improvements in brightness (L*) and redness (a*), P<0.05. Self-assessed aging parameters were significantly improved on the décolletage and neck, P<0.05. Digital photography demonstrated obvious antiaging effects including improved texture of neck and décolletage areas, reduced appearance of lines and wrinkles, reduced mottled hyperpigmentation, and a more youthful, firm appearance. The test cream was well-tolerated with no significant changes in irritation parameters throughout the study. CONCLUSION: The antiaging neck/décolletage cream delivered significant firming and smoothing effects with reduced appearance of hyperpigmentation and can be considered an effective topical homecare treatment option for patients seeking rejuvenation of this challenging area

Effects of N-acetyl glucosamine and chondroitin sulfate supplementation on knee pain and self-reported knee function in middle-aged and older Japanese adults: a randomized, double-blind, placebo-controlled trial.

BACKGROUND: There was no evidence of satisfying the standard to decide the efficacies of glucosamine and chondroitin in middle-aged and older Japanese adults with knee pain and/or stiffness. AIM: To investigate the effects of 24 week oral N-acetyl glucosamine and chondroitin sulfate supplementation on knee pain, self-reported knee function, physical activity, and physical performance. METHODS: We randomly assigned 11 men and 39 women (aged 52-87 years) to receive 100 mg of N-acetyl glucosamine and 180 mg of chondroitin sulfate daily (Glu/Cho group) or a placebo (control, C group) for 24 weeks. The primary outcomes were a 100 mm visual analog pain scale (VAS) and the Japanese Knee Osteoarthritis Measure (JKOM) score. The secondary outcomes were physical activity and physical performance. RESULTS: We observed a significant group × time interaction on the JKOM score. According to the post hoc test, it significantly decreased (i.e., improved knee function) from the 4- to 12-week follow-up in the Glu/Cho group and the Glu/Cho group score was significantly lower than the C group at the 12-week follow-up. We found a significant interaction on household physical activity. There was no significant interaction on VAS or physical performance tests. DISCUSSION: The results of the present study were consistent with previous studies mainly conducted in European and American countries. CONCLUSION: These results suggest that consumption of N-acetyl glucosamine and chondroitin sulfate for 12 weeks or longer has a positive effect on self-reported knee function and household physical activity in middle-aged and older Japanese adults with knee pain and/or stiffness.

You are what you eat: O-linked N-acetylglucosamine in disease, development and epigenetics.

PURPOSE OF REVIEW: The O-linked N-acetylglucosamine (O-GlcNAc) modification is both responsive to nutrient availability and capable of altering intracellular cellular signalling. We summarize data defining a role for O-GlcNAcylation in metabolic homeostasis and epigenetic regulation of development in the intrauterine environment. RECENT FINDINGS: O-GlcNAc transferase (OGT) catalyzes nutrient-driven O-GlcNAc addition and is subject to random X-inactivation. OGT plays key roles in growth factor signalling, stem cell biology, epigenetics and possibly imprinting. The O-GlcNAcase, which removes O-GlcNAc, is subject to tight regulation by higher order chromatin structure. O-GlcNAc cycling plays an important role in the intrauterine environment wherein OGT expression is an important biomarker of placental stress. SUMMARY: Regulation of O-GlcNAc cycling by X-inactivation, epigenetic regulation and nutrient-driven processes makes it an ideal candidate for a nutrient-dependent epigenetic regulator of human disease. In addition, O-GlcNAc cycling influences chromatin modifiers critical to the regulation and timing of normal development including the polycomb repression complex and the ten-eleven translocation proteins mediating DNA methyl cytosine demethylation. The pathway also impacts the hypothalamic-pituitary-adrenal axis critical to intrauterine programming influencing disease susceptibility in later life.

The repair of full-thickness articular cartilage defect using intra-articular administration of N-acetyl-D-glucosamine in the rabbit knee: randomized controlled trial.

BACKGROUND: Although various alterative models of therapy are used for cartilage repair, no definite conclusion has been reached. Glucosamine (GlcN) is widely used as a nutritional supplement. However, the clinical- evidence-based outcome of GlcN administration remains controversial. N-acetyl-D-glucosamine (GlcNAc), a derivative of GlcN, shows chondroprotective activity and mediates the activation of articular chondrocytes. Therefore, we investigated the effect of intra-articular administration of GlcNAc in rabbits' knee joints with experimental full-thickness articular cartilage (FTAC) defects. METHODS: Twelve male adult New Zealand white rabbits, providing 24 knees, were used in this study. FTAC defects were created in the high-weight-bearing area of the medial femoral condyles of bilateral knees. All rabbits were randomly allocated to analysis at postsurgical week 4 or postsurgical week 12. In the week 4 group, rabbits' knees (six per group) were intra-articularly injected with normal saline or with GlcNAc twice per week for 3 weeks, beginning 1 week postoperatively. In the week 12 group, the rabbits' knees (six in each group) were intra-articularly injected with normal saline or with GlcNAc twice per week for 4 weeks, beginning 1 week postoperatively. Rabbits were sacrificed at 4 or 12 weeks after surgery for macroscopic, histological and radiological examinations of the knee joints. RESULTS: All rabbits had no systemic or local adverse effects. The saline and GlcNAc groups showed visible differences in healing of the FTAC defect at the end of testing. At week 4, the GlcNAc group had a higher level of collagen type II (COL II) and showed up-regulated production of transforming growth factor (TGF)-ß2 and TGF-ß3, suggesting the involvement of endogenous growth factors. At week 12, the GlcNAc group displayed formation of hyaline-like cartilage regeneration with mature chondrocytes (SOX9+), robust glycosaminoglycan (GAG) content, and positive COL II content in both the adjacent cartilage and reparative sites. However, the saline group demonstrated mainly fibrocartilage scar tissue, indicating COL I expression. Furthermore, the GlcNAc group had significantly higher bone volume per tissue volume and higher trabecular thickness than the saline group. CONCLUSIONS: Intra-articular GlcNAc may promote the repair of experimental FTAC defects in the rabbit knee joint model.

Neocollagenesis in Deep and Superficial Dermis by Combining Fractionated Q-Switched ND:YAG 1,064-nm With Topical Plant Stem Cell Extract and N-Acetyl Glucosamine: Open Case Series.

INTRODUCTION: As we enter a new age of increasing demand in novel cosmetic therapies, we are challenged to provide excellent results with minimal downtime and safety in all skin types. In this open case series we are studying the improvement in rhytides by combining a novel, FDA-approved, non-ablative fractionated Q-switched ND: YAG 1,064-nm laser that acts in the deep dermis, with a topical containing plant stem cell extract and N-acetyl glucosamine (NAG) that acts in the superficial dermis. METHOD: Six healthy females (Skin types III - V) were selected for the study with mean average age of 56 years +/- 11 years. The rhytides on the face and neck were assessed using a comprehensive grading scale. Patients were then divided into two groups, one received only laser treatment with the fractionated QSW 1,064 nm laser and the other group received combined treatment with the laser and topical. Patients were assessed again at 4 and 8 weeks. RESULTS: We observed an enhanced anti-aging effect of the laser in the patients with combined treatment. DISCUSSION: Understanding the effect of this novel laser therapy on human stem cells and investigating the basis of its synergistic effect with plant stem cell extract and NAG will lead us to better understand stem cell activity. Non-ablative tissue regeneration is the next step in providing optimal anti-aging treatments.

Metabolomic Analysis of Blood Plasma after Oral Administration of N-acetyl-d-Glucosamine in Dogs.

N-acetyl-d-glucosamine (GlcNAc) is a monosaccharide that polymerizes linearly through (1,4)-ß-linkages. GlcNAc is the monomeric unit of the polymer chitin. GlcNAc is a basic component of hyaluronic acid and keratin sulfate found on the cell surface. The aim of this study was to examine amino acid metabolism after oral GlcNAc administration in dogs. Results showed that plasma levels of ectoine were significantly higher after oral administration of GlcNAc than prior to administration (p < 0.001). To our knowledge, there have been no reports of increased ectoine concentrations in the plasma. The mechanism by which GlcNAc administration leads to increased ectoine plasma concentration remains unclear; future studies are required to clarify this mechanism.

Collagen-induced arthritis: severity and immune response attenuation using multivalent N-acetyl glucosamine.

Rheumatoid arthritis is an autoimmunity leading to considerable impairment of quality of life. N-acetyl glucosamine (GlcNAc) has been described previously as a potent modulator of experimental arthritis in animal models and is used for osteoarthritis treatment in humans, praised for its lack of adverse effects. In this study we present a comprehensive immunological analysis of multivalent GlcNAc-terminated glycoconjugate (GC) application in the treatment of collagen-induced arthritis (CIA) and its clinical outcome. We used immunohistochemistry and FACS to describe conditions on the inflammation site. Systemic and clinical effects were evaluated by FACS, cytotoxicity assay, ELISA, cytometric bead array (CBA), RT-PCR and clinical scoring. We found reduced inflammatory infiltration, NKG2D expression on NK and suppression of T, B and antigen-presenting cells (APC) in the synovia. On the systemic level, GCs prevented the activation of monocyte- and B cell-derived APCs, the rise of TNF-α and IFN-γ levels, and subsequent type II collagen (CII)-specific IgG2a formation. Moreover, we detected an increase of anti-inflammatory IL-4 mRNA in the spleen. Similar to the synovia, the GCs caused a significant reduction of NKG2D-expressing NK cells in the spleen without influencing their lytic function. GCs effectively postponed the onset of arthritic symptoms, reduced their severity and in 18% (GN8P) and 31% (GN4C) of the cases completely prevented their appearance. Our data prove that GlcNAc glycoconjugates prevent the inflammatory response, involving proinflammatory cytokine rise, APC activation and NKG2D expression, leading to the attenuation of clinical symptoms. These results support the glycobiological approach to the treatment of collagen-induced arthritis/rheumatoid arthritis (CIA/RA) as a way of bringing new prospects for more effective therapeutic interventions.

Treatment of experimentally induced osteoarthritis in horses using an intravenous combination of sodium pentosan polysulfate, N-acetyl glucosamine, and sodium hyaluronan.

OBJECTIVE: To assess the effects of sodium pentosan polysulfate (PPS), N-acetyl glucosamine (NAG), and sodium hyaluronan (HA) in horses with induced osteoarthritis (OA). STUDY DESIGN: Experimental. ANIMALS: Adult Standard bred horses (n = 16). METHODS: OA was induced arthroscopically in 1 intercarpal joint; 8 horses were administered 3 mg/kg PPS, 4.8 mg/kg NAG, and 0.12 mg/kg HA (PGH), intravenously (IV), weekly and 8 horses were administered an equivalent volume of saline IV until study completion (day 70). Horses underwent a standardized treadmill exercise program. Clinical and radiographic findings and synovial fluid analysis were evaluated throughout the study. Macroscopic, histologic, histochemical, and biochemical findings were evaluated after necropsy. Comparisons of interest included OA and non-OA joints of saline treated horses and OA joints of PGH treated horses and OA joints of saline treated horses. Results were statistically analyzed with significance set at P < .05. RESULTS: OA caused increases in clinical assessment scores, synovial fluid variables, radiographic, macroscopic, and histologic cartilage scores, synovial fluid and cartilage chondroitin sulfate 846-epitope and glycosaminoglycan concentration. Total radiographic scores, total macroscopic joint pathology and macroscopic cartilage pathology scores were significantly reduced in horses treated with PGH compared with saline treated horses. Synovial fluid total protein concentration and white blood cell count were higher in OA joints of PGH treated horses compared with saline treated horses. There were no other significant differences between treatment groups. CONCLUSIONS: Improvements in macroscopic variables were not supported by other outcomes. Further evidence is needed before PGH can be recommended as a therapeutic option for osteoarthritis in horses.

N-acetylglucosamine increases symptoms and fungal burden in a murine model of oral candidiasis.

The amino sugar N-acetylglucosamine (GlcNAc) is an in vitro inducer of the hyphal mode of growth of the opportunistic pathogen Candida albicans. The development of hyphae by C. albicans is considered to contribute to the pathogenesis of mucosal oral candidiasis. GlcNAc is also a commonly used nutritional supplement for the self-treatment of conditions such as arthritis. To date, no study has investigated whether ingestion of GlcNAc has an effect on the in vivo growth of C. albicans or the pathogenesis of a C. albicans infection. Using a murine model of oral candidiasis, we have found that administration of GlcNAc, but not glucose, increased oral symptoms of candidiasis and fungal burden. Groups of mice were given GlcNAc in either water or in a viscous carrier, i.e., 1% methylcellulose. There was a dose-dependent relationship between GlcNAc concentration and the severity of oral symptoms. Mice given the highest dose of GlcNAc, 45.2 mM, also showed a significant increase in fungal burden, and increased histological evidence of infection compared to controls given water alone. We propose that ingestion of GlcNAc, as a nutritional supplement, may have an impact on oral health in people susceptible to oral candidiasis.

Transdermal permeation of novel n-acetyl-glucosamine/NSAIDs mutual prodrugs.

The current investigation reports skin permeation of three novel mutual prodrugs (MP) which couple n-acetyl-glucosamine with an NSAID, either ketoprofen or ibuprofen. They were evaluated for transdermal permeation using shed snakeskin, and to our knowledge represent the first MPs synthesized for this purpose, although they also could be used for subcutaneous delivery. MPs are defined as two active drug compounds usually connected by an ester linkage. Glucosamine administration has been linked to damaged cartilage repair, and pain relief in joints afflicted with osteoarthritis. NSAIDs are commonly used orally in transdermal creams or gels for joint pain relief. Two novel compounds we report (MP1 and MP2) covalently link ibuprofen and ketoprofen directly to the amide nitrogen of n-acetyl-glucosamine (NAG); the other compound (MP3) covalently links ibuprofen to the amide nitrogen, using a short chain acetyl linker. Permeability studies show that the ketoprofen mutual prodrug (MP2) permeates shed snakeskin more than three times greater than either ibuprofen derivative, while ethanol markedly increases the permeation for all three. The ketoprofen mutual prodrug appears the most likely candidate for transdermal administration; all three mutual prodrugs may be candidates for subcutaneous injection.

Serum Antibody Activity against Poly-N-Acetyl Glucosamine (PNAG), but Not PNAG Vaccination Status, Is Associated with Protecting Newborn Foals against Intrabronchial Infection with Rhodococcus equi.

Rhodococcus equi is a prevalent cause of pneumonia in foals worldwide. Our laboratory has demonstrated that vaccination against the surface polysaccharide ß-1→6-poly-N-acetylglucosamine (PNAG) protects foals against intrabronchial infection with R. equi when challenged at age 28 days. However, it is important that the efficacy of this vaccine be evaluated in foals when they are infected at an earlier age, because foals are naturally exposed to virulent R. equi in their environment from birth and because susceptibility is inversely related to age in foals. Using a randomized, blind experimental design, we evaluated whether maternal vaccination against PNAG protected foals against intrabronchial infection with R. equi 6 days after birth. Vaccination of mares per se did not significantly reduce the incidence of pneumonia in foals; however, activities of antibody against PNAG or for deposition of complement component 1q onto PNAG was significantly (P < 0.05) higher among foals that did not develop pneumonia than among foals that developed pneumonia. Results differed between years, with evidence of protection during 2018 but not 2020. In the absence of a licensed vaccine, further evaluation of the PNAG vaccine is warranted, including efforts to optimize the formulation and dose of this vaccine. IMPORTANCE Pneumonia caused by R. equi is an important cause of disease and death in foals worldwide for which a licensed vaccine is lacking. Foals are exposed to R. equi in their environment from birth, and they appear to be infected soon after parturition at an age when innate and adaptive immune responses are diminished. Results of this study indicate that higher activity of antibodies recognizing PNAG was associated with protection against R. equi pneumonia, indicating the need for further optimization of maternal vaccination against PNAG to protect foals against R. equi pneumonia.

Reduction in the appearance of facial hyperpigmentation after use of moisturizers with a combination of topical niacinamide and N-acetyl glucosamine: results of a randomized, double-blind, vehicle-controlled trial.

BACKGROUND: Topical niacinamide and N-acetyl glucosamine (NAG) each individually inhibit epidermal pigmentation in cell culture. In small clinical studies, niacinamide-containing and NAG-containing formulations reduced the appearance of hyperpigmentation. OBJECTIVES: To assess the effect of a combination of niacinamide and NAG in a topical moisturizing formulation on irregular facial pigmentation, including specific detection of changes in colour features associated with melanin. METHODS: This was a 10-week, double-blind, vehicle-controlled, full-face, parallel-group clinical study conducted in women aged 40-60 years. After a 2-week washout period, subjects used a daily regimen of either a morning sun protection factor (SPF) 15 sunscreen moisturizing lotion and evening moisturizing cream each containing 4% niacinamide + 2% NAG (test formulation; n = 101) or the SPF 15 lotion and cream vehicles (vehicle control; n = 101). Product-induced changes in apparent pigmentation were assessed by capturing digital photographic images of the women after 0, 4, 6 and 8 weeks of product use and evaluating the images by algorithm-based computer image analysis for coloured spot area fraction, by expert visual grading, and by chromophore-specific image analysis based on noncontact SIAscopy for melanin spot area fraction and melanin chromophore evenness. RESULTS: By all four measures, the niacinamide + NAG formulation regimen was significantly (P < 0.05) more effective than the vehicle control formulation regimen in reducing the detectable area of facial spots and the appearance of pigmentation. CONCLUSIONS: A formulation containing the combination of niacinamide + NAG reduced the appearance of irregular pigmentation including hypermelaninization, providing an effect beyond that achieved with SPF 15 sunscreen.

N-acetyl-d-glucosamine-conjugated PAMAM dendrimers as dual receptor-targeting nanocarriers for anticancer drug delivery.

N-acetyl-d-glucosamine-labelled dendrimers (NAG-Dend) were synthesized for the targeted delivery of camptothecin (CPT) to A549 human lung adenocarcinoma cells, which overexpress glucose transporters and lectin receptors. CPT loaded, NAG-Dend (NAG-Dend-CPT) exhibited more rapid and higher cellular uptake than the unlabelled dendrimer formulation (Dend-CPT), leading to enhanced cytotoxicity. Compared with native CPT, NAG-Dend-CPT was 4.5 times more toxic to A549 cells. The anticancer activity of the different CPT formulations was dose and time dependent. NAG-Dend-CPT also increased reactive oxygen species generation, induced higher apoptosis and showed greater inhibition of A549 cell migration than Dend-CPT. The selective accumulation of NAG-Dend in the lungs of tumour-bearing mice confirmed that the NAG-based dendrimer system can target lung metastasis tumours in a biological system. Overall, our results show that NAG-conjugated dendrimers could be a promising nanocarrier system for the delivery of anticancer drugs, including CPT, to human lung cancer cells.