The PI3K-Akt-mTOR and Associated Signaling Pathways as Molecular Drivers of Immune-Mediated Inflammatory Skin Diseases: Update on Therapeutic Strategy Using Natural and Synthetic Compounds

The dysregulated phosphatidylinositol-3-kinase (PI3K)-Akt-mammalian target of rapamycin (mTOR) signaling pathway has been implicated in various immune-mediated inflammatory and hyperproliferative dermatoses such as acne, atopic dermatitis, alopecia, psoriasis, wounds, and vitiligo, and is associated with poor treatment outcomes. Improved comprehension of the consequences of the dysregulated PI3K/Akt/mTOR pathway in patients with inflammatory dermatoses has resulted in the development of novel therapeutic approaches. Nonetheless, more studies are necessary to validate the regulatory role of this pathway and to create more effective preventive and treatment methods for a wide range of inflammatory skin diseases. Several studies have revealed that certain natural products and synthetic compounds can obstruct the expression/activity of PI3K/Akt/mTOR, underscoring their potential in managing common and persistent skin inflammatory disorders. This review summarizes recent advances in understanding the role of the activated PI3K/Akt/mTOR pathway and associated components in immune-mediated inflammatory dermatoses and discusses the potential of bioactive natural products, synthetic scaffolds, and biologic agents in their prevention and treatment. However, further research is necessary to validate the regulatory role of this pathway and develop more effective therapies for inflammatory skin disorders.

Dual targeting of mTOR/IL-17A and autophagy by fisetin alleviates psoriasis-like skin inflammation

Psoriasis is a chronic autoimmune inflammatory skin disorder characterized by epidermal hyperplasia and aberrant immune response. In addition to aberrant cytokine production, psoriasis is associated with activation of the Akt/mTOR pathway. mTOR/S6K1 regulates T-lymphocyte activation and migration, keratinocytes proliferation and is upregulated in psoriatic lesions. Several drugs that target Th1/Th17 cytokines or their receptors have been approved for treating psoriasis in humans with variable results necessitating improved therapies. Fisetin, a natural dietary polyphenol with anti-oxidant and anti-proliferative properties, covalently binds mTOR/S6K1. The effects of fisetin on psoriasis and its underlying mechanisms have not been clearly defined. Here, we evaluated the immunomodulatory effects of fisetin on Th1/Th17-cytokine-activated adult human epidermal keratinocytes (HEKa) and anti-CD3/CD28-stimulated inflammatory CD4+ T cells and compared these activities with those of rapamycin (an mTOR inhibitor). Transcriptomic analysis of HEKa revealed 12,713 differentially expressed genes (DEGs) in the fisetin-treated group compared to 7,374 DEGs in the rapamycin-treated group, both individually compared to a cytokine treated group. Gene ontology analysis revealed enriched functional groups related to PI3K/Akt/mTOR signaling pathways, psoriasis, and epidermal development. Using in silico molecular modeling, we observed a high binding affinity of fisetin to IL-17A. In vitro, fisetin significantly inhibited mTOR activity, increased the expression of autophagy markers LC3A/B and Atg5 in HEKa cells and suppressed the secretion of IL-17A by activated CD4+ T lymphocytes or T lymphocytes co-cultured with HEKa. Topical administration of fisetin in an imiquimod (IMQ)-induced mouse psoriasis model exhibited a better effect than rapamycin in reducing psoriasis-like inflammation and Akt/mTOR phosphorylation and promoting keratinocyte differentiation and autophagy in mice skin lesions. Fisetin also significantly inhibited T-lymphocytes and F4/80+ macrophage infiltration into skin. We conclude that fisetin potently inhibits IL-17A and the Akt/mTOR pathway and promotes keratinocyte differentiation and autophagy to alleviate IMQ-induced psoriasis-like disease in mice. Altogether, our findings suggest fisetin as a potential treatment for psoriasis and possibly other inflammatory skin diseases.

Association of diet with clinical outcomes in dogs with dilated cardiomyopathy and congestive heart failure

INTRODUCTION

Dilated cardiomyopathy (DCM) in dogs has been associated with feeding of grain-free (GF), legume-rich diets. Some dogs with presumed diet-associated DCM have shown improved myocardial function and clinical outcomes following a change in diet and standard medical therapy.

HYPOTHESIS

Prior GF (pGF) diet influences reverse cardiac remodeling and clinical outcomes in dogs with DCM and congestive heart failure (CHF).

ANIMALS AND METHODS

A retrospective study was performed with 67 dogs with DCM and CHF for which diet history was known. Dogs were grouped by diet into pGF and grain-inclusive (GI) groups. Dogs in the pGF group were included if diet change was a component of therapy. Survival was analyzed using Kaplan-Meier curves and the Cox proportional-hazards model.

RESULTS

The median survival time was 344 days for pGF dogs vs. 253 days for GI dogs (P = 0.074). Statistically significant differences in median survival were identified when the analysis was limited to dogs surviving longer than one week (P = 0.033). Prior GF dogs had a significantly worse outcome the longer a GF diet was fed prior to diagnosis (P = 0.004) or if they were diagnosed at a younger age (P = 0.017). Prior GF dogs showed significantly greater improvement in normalized left ventricular internal diastolic diameter (P = 0.038) and E-point septal separation (P = 0.031) measurements and significant decreases in their furosemide (P = 0.009) and pimobendan (P < 0.005) dosages over time compared to GI dogs.

CONCLUSIONS

Prior GF dogs that survived at least one week after diagnosis of DCM, treatment of CHF, and diet change had better clinical outcomes and showed reverse ventricular remodeling compared to GI dogs.

Synthesis, inverse docking-assisted identification and in vitro biological characterization of Flavonol-based analogs of fisetin as c-Kit, CDK2 and mTOR inhibitors against melanoma and non-melanoma skin cancers

Due to hurdles, including resistance, adverse effects, and poor bioavailability, among others linked with existing therapies, there is an urgent unmet need to devise new, safe, and more effective treatment modalities for skin cancers. Herein, a series of flavonol-based derivatives of fisetin, a plant-based flavonoid identified as an anti-tumorigenic agent targeting the mammalian targets of rapamycin (mTOR)-regulated pathways, were synthesized and fully characterized. New potential inhibitors of receptor tyrosine kinases (c-KITs), cyclin-dependent kinase-2 (CDK2), and mTOR, representing attractive therapeutic targets for melanoma and non-melanoma skin cancers (NMSCs) treatment, were identified using inverse-docking, in vitro kinase activity and various cell-based anticancer screening assays. Eleven compounds exhibited significant inhibitory activities greater than the parent molecule against four human skin cancer cell lines, including melanoma (A375 and SK-Mel-28) and NMSCs (A431 and UWBCC1), with IC50 values ranging from 0.12 to < 15 μM. Seven compounds were identified as potentially potent single, dual or multi-kinase c-KITs, CDK2, and mTOR kinase inhibitors after inverse-docking and screening against twelve known cancer targets, followed by kinase activity profiling. Moreover, the potent compound F20, and the multi-kinase F9 and F17 targeted compounds, markedly decreased scratch wound closure, colony formation, and heightened expression levels of key cancer-promoting pathway molecular targets c-Kit, CDK2, and mTOR. In addition, these compounds downregulated Bcl-2 levels and upregulated Bax and cleaved caspase-3/7/8 and PARP levels, thus inducing apoptosis of A375 and A431 cells in a dose-dependent manner. Overall, compounds F20, F9 and F17, were identified as promising c-Kit, CDK2 and mTOR inhibitors, worthy of further investigation as therapeutics, or as adjuvants to standard therapies for the control of melanoma and NMSCs.

Role and Therapeutic Targeting of the PI3K/Akt/mTOR Signaling Pathway in Skin Cancer: A Review of Current Status and Future Trends on Natural and Synthetic Agents Therapy

The mammalian or mechanistic target of rapamycin (mTOR) and associated phosphatidyl-inositiol 3-kinase (PI3K)/protein kinase B (Akt) pathways regulate cell growth, differentiation, migration, and survival, as well as angiogenesis and metabolism. Dysregulation of these pathways is frequently associated with genetic/epigenetic alterations and predicts poor treatment outcomes in a variety of human cancers including cutaneous malignancies like melanoma and non-melanoma skin cancers. Recently, the enhanced understanding of the molecular and genetic basis of skin dysfunction in patients with skin cancers has provided a strong basis for the development of novel therapeutic strategies for these obdurate groups of skin cancers. This review summarizes recent advances in the roles of PI3K/Akt/mTOR and their targets in the development and progression of a broad spectrum of cutaneous cancers and discusses the current progress in preclinical and clinical studies for the development of PI3K/Akt/mTOR targeted therapies with nutraceuticals and synthetic small molecule inhibitors.

Role of induced negative and positive emotions in sensitivity to itch and pain in women

BACKGROUND

Itch and pain are common symptoms in skin disease. It has been suggested that negative emotions may play a role in itch and pain. To date, however, the role of emotions has only been studied for pain in experimental studies, not yet for itch.

OBJECTIVES

To investigate the effects of negative and positive emotions on the sensitivity to itch and pain.

METHODS

Film fragments were used to induce a negative or positive emotional state in healthy women. Itch and pain were induced using the following somatosensory stimuli: electrical stimulation, histamine iontophoresis and the cold pressor test.

RESULTS

Results showed that the scores for itch and pain evoked by histamine and the cold pressor test, respectively, were significantly higher in the negative than in the positive emotion condition, whereas tolerance thresholds to electrical stimulation and the cold pressor test, and stimulus unpleasantness scores did not differ between the two conditions.

CONCLUSIONS

These findings for the first time indicate in an experimental design that emotions play a role in sensitivity to somatosensory sensations of both itch and pain.

A case report on fixation instability in Parkinson's disease with bilateral deep brain stimulation implants

We report on fixation instabilities in a patient diagnosed with Parkinson's disease (PD). This patient underwent deep brain stimulation (DBS) surgery bilaterally in the vicinity of the subthalamic nuclei (STN). Examination of the eye movements of this patient revealed marked fixation instability compared with a healthy age matched control. The eye movements occurring during fixation differed from other reports of fixation instabilities in that they interrupted fixation for only brief durations. These interruptive saccades (IS) had saccade-like amplitude velocity relationships. The frequency of these IS was higher in the patient with PD than in the healthy age matched control. Furthermore, the frequency of the IS in the patient reduced toward control with application of bilateral DBS in the vicinity of the STN. From our observations we conclude that fixation ability may be altered in PD and improved with DBS.

Patterns, incidence and predictive factors for pain after interventional radiology

AIM

To evaluate prospectively the pattern, severity and predictive factors of pain after interventional radiological procedures.

MATERIALS AND METHODS

All patients undergoing non-arterial radiological interventional procedures were assessed using a visual-analogue scale (VAS) for pain before and at regular intervals for 24 h after their procedure.

RESULTS

One hundred and fifty patients (87 men, mean age 62 years, range 18-92 years) were entered into the study. Significant increases in VAS score occurred 8 h after percutaneous biliary procedures (+47.7 mm, SD 14.9 mm; p=0.001), 6 h after central venous access and gastrostomy insertion (+23.7 mm, SD 19.5 mm; p=0.001 and +28.4 mm, SD 9.7 mm; p=0.007, respectively) and 4h after oesophageal stenting (+27.8 mm, SD 20.2 mm, p=0.001). Non-significant increases in VAS pain score were observed after duodenal and colonic stenting (duodenal: +5.13 mm, SD 7.47 mm; p=0.055, colonic: +23.3 mm, SD 13.10 mm, p=0.250) at a mean of 5h (range 4-6h). Patients reported a significant reduction in pain score for nephrostomy insertion (-28.4mm, SD 7.11 mm, p=0.001). Post-procedural analgesia was required in 99 patients (69.2%), 40 (28.0%) requiring opiates. Maximum post-procedural VAS pain score was significantly higher in patients who had no pre-procedural analgesia (p=0.003).

CONCLUSION

Post-procedural pain is common and the pattern and severity of pain between procedures is variable. Pain control after interventional procedures is often inadequate, and improvements in pain management are required.

6,6′-Bis(2-hydroxyphenyl)-2,2′-bipyridine manganese(III) complexes: A novel series of superoxide dismutase and catalase mimetics

A series of novel manganese(III) complexes is described based on a 6,6'-bis(2-hydroxyphenyl)-2,2'-bipyridine template. These complexes show superoxide dismutase and catalase activity. The effect of the aromatic substitution pattern on the SAR is described.

Vision readiness at Seymour Johnson Air Force Base

Ensuring that our forces are vision ready, i.e., they have the appropriate visual acuity, optical devices, and eye health to perform their mission, is essential on today's battlefield. A study was conducted at Seymour Johnson Air Force Base to determine the prevalence of vision readiness in a deploying fighter squadron. Of the 204 personnel screened, 59 wore glasses or contact lenses. Of these 59, 15 individuals (25%) were optically ready and 44 individuals (75%) were not optically ready to deploy. Optical readiness is defined as having the correct type and number of optical devices. Of the 15 individuals (25%) who were optically ready, 13 (87%) had had a professional eye examination within 12 months. Of the 44 individuals (75%) who were not optically ready, 36 (82%) had been examined within 1 year. Pearson's chi 2 test (chi 2 = 1.59, degrees of freedom = 3, significance = 0.66) indicated that there was no significant association between readiness and the date of the last examination. This study reveals that although personnel are having regular periodic professional eye examinations, optometry personnel, commanders, and deploying airmen must take a more active role in ensuring that our forces are vision ready.

Bacteria associated with pyothorax of dogs and cats: 98 cases (1989-1998)

OBJECTIVE

To determine the organisms most commonly isolated from pleural fluid from dogs and cats with pyothorax.

DESIGN

Retrospective study.

ANIMALS

51 dogs and 47 cats.

PROCEDURE

Results of bacteriologic culture of pleural fluid samples obtained by means of thoracentesis were obtained from medical records. To obtain information on in vitro antimicrobial susceptibility of organisms commonly isolated from dogs and cats, records of all dogs and cats examined during 1998 were reviewed, and information was obtained on identity and in vitro antimicrobial susceptibility of aerobic organisms isolated from samples other than urine or urinary tract samples.

RESULTS

Median ages of dogs and cats were 4 years. Bacteria were isolated from pleural fluid samples from 47 of 51 (92%) dogs and 45 of 47 (96%) cats. Obligate anaerobic bacteria were isolated from 28 dogs and 40 cats. A mixture of obligate anaerobic and facultative bacteria was isolated from 17 dogs and 20 cats. Samples from cats most often yielded a member of the nonenteric group (most commonly members of the genus Pasteurella), whereas those from dogs more often yielded a member of the family Enterobacteriaceae (most commonly E coli).

CONCLUSIONS AND CLINICAL RELEVANCE

Results suggest that antimicrobial agents chosen for the initial treatment of dogs and cats with pyothorax should be active against a mixture of obligate anaerobic and facultative bacteria.

Signal transduction by B and T cells early after bone marrow transplantation: B cell calcium flux responses are intact whereas lack of CD4 cells accounts for impaired T cell responses

We previously found that intracellular ionized calcium ([Ca2+]i) flux responses after anti-CD3 crosslinking of CD3/TCR on T cells from allogeneic and autologous bone marrow transplant (BMT) recipients were impaired, Yamagami et al. J Clin Invest 1990; 86: 1347-1351. In contrast to the earlier study, this study focuses on identifying the T cell subset(s) responsible for the defects and determining if B cell responses are defective in BMT recipients early after BMT. In 37 recipients after anti-CD3 stimulation of PBL, a mean of 25.9% responding T cells was observed. This was significantly lower than the mean of 43.6% responding T cells in PBL from 21 normals (P < 0.001). The proportion of responding T cells in PBL (T PBL) increased in the recipients with time after BMT. By 6 months after BMT, the mean percent of responding T PBL approached the normal range. On the other hand, a mean of 8.1% responding B cells in anti-IgM crosslinked PBL from 24 recipients was not different from the mean of 7.4% responding B cells in anti-IgM crosslinked PBL from 16 normals (P = 0.6). Four color flow cytometry was used to identify subpopulations of lymphocytes. Enriched B cells were tested by gating out CD3+ and CD56+ cells to confirm the results of unfractionated PBL. In 8 recipients, the mean percent responding B cells was 36.6% and was not different from 6 normals (mean = 41.0%).(ABSTRACT TRUNCATED AT 250 WORDS)

The anatomy of the inferior petrosal sinus, glossopharyngeal nerve, vagus nerve, and accessory nerve in the jugular foramen

PURPOSE

To define the variations of the courses of the cranial nerves and the inferior petrosal sinuses as they enter and traverse the jugular foramen.

METHODS

Thirty-nine cadaveric specimens containing the jugular foramen were scanned with 1-mm contiguous axial and coronal CT sections. Each specimen was dissected to evaluate the position of the cranial nerves and inferior petrosal sinus as they entered the jugular foramen.

RESULTS

The glossopharyngeal nerve entered the most superior, anterior, and medial aspect of the jugular foramen and descended in the anterior portion of the jugular foramen, often within a groove. The vagus and accessory nerves could not be separated by CT. They entered the jugular foramen most often anterior or anterior and inferior to the jugular spine of the temporal bone and descended in a position ranging from medial to anterior to the jugular vein. The inferior petrosal sinus most often coursed inferior to the horizontal portion of the glossopharyngeal nerve and entered the jugular system in the jugular foramen, at the exocranial opening or below the skull base. A pars nervosa and pars venosa could be identified only at the endocranial opening, where the jugular spine separated the pars nervosa containing the inferior petrosal sinus and three cranial nerves from the pars venosa containing the jugular vein.

CONCLUSION

Our evaluation demonstrated anatomic variation in the area of the jugular foramen.

The short-term effects of a fire safety education program for the elderly

The high risk of fire death and injury among elderly people is well documented. To be effective, fire safety education must reach older adults in the settings in which they reside: nursing homes and other long-term care institutions, board and care homes, and independent living facilities including the person's own home. Training must also be targeted at the people who are responsible for fire safety. In the case of the nursing home or board and care home, the responsible people are the staff and owners. In the case of the majority of older adults who live independently in their homes, it is either the individual or family members. These programs must also be comprehensive. A fire safety education curriculum was developed by a group of experts in a variety of related fields including fire safety, gerontology, health care industry, developmental disabilities, research, and instructional design. Older adults were included in each planning session. Based on that curriculum, workshops and workshop materials were developed for each of the three target populations: staff of health care facilities, staff and owners of board and care homes, and elderly people living independently in their homes. Materials included both print and audiovisuals. A pilot test of each workshop was conducted to test the short-term effects of the programs. Results indicated significant gains in knowledge for all groups and a significant improvement in positive attitudes toward fire safety for most participants. Measures of effects of the programs on intentions to change fire safety practices indicated a potential for change. Results also showed that the measured traits, knowledge of fire safety and attitudes toward fire safety, were relatively stable.