Current Pharmaceutical Biotechnology - Volume 15, Issue 8, 2014

Objective: We sought to evaluate the safety of imipenem and meropenem in the treatment of infections in neurosurgical patients. Methods: An observational retrospective study was conducted of consecutive cases treated with imipenem from Sept. 2007 to Sept. 2009 and meropenem within 1 year from Sept. 2008 in Beijing Tiantan Hospital, China. Data including the dosage and duration of the drug use, occurrence of seizures and mortality outcome was collected from the electronic pharmacy records. The incidence of epilepsy, epileptic standardized morbidity rate (SMR) were reported. Attention was paid to the relationship between the use of imipenem/meropenem and the incidence of epilepsy. Results: The imipenem patients within two years amounted to 71, with mean age 45.9±20.2 years, male to female ratio 46/25. The incidence of epilepsy was 11.3% (8 cases). Among them, 1 case occurred during treatment (1/633, 1.6/1000 patient-days), and the remaining 7 cases occurred before treatment (7/2819, 2.5/1000 patient-days), with the standardized incidence rate 0.64, 95% CI (0.08-5.18).The meropenem patients within one year amounted to 92, mean age 45.1±19.4 years, male to female ratio 51/41. The incidence of epilepsy was 6.5% (6 cases). 2 occurred during treatment (2/582, 2.0/1000 patients-hospital days) and 4 before treatment (4/2047, 3.4/1000 patients-inpatient days), standardized incidence rate 1.76, 95% CI (0.32-9.63). Conclusion: Despite many other epileptogenic factors, imipenem or meropenem did not increase the risk of seizures in neurosurgical patients. There was not further risk for patients with pre-existing seizures or creatinine clearance abnormalities when dosed appropriate.

An in silico screening method for novel dipeptides from a dipeptide training set was performed. A 3D pharmacophore model with three H-bond acceptor projections (Acc2), and one H-bond donor projection (Don2) was obtained. To validate the pharmacophore model, a test set containing 10 reported dipeptides was screened and all were found to be bioactive. Eleven novel dipeptides (IF, GD, DA, TE, TA, ES, SS, ST, SD, QD, QE) from the silkworm pupae protein peptide database were predicted to have ACE inhibitory bioactivity. The interaction mechanisms of the dipeptides with the ACE active pocket were elucidated by molecule docking, and besides involving interaction bonds, the interaction force equipoise of the peptides was also an important factor in their bioactivity.

Platonin, a photosensitizing dye, is known to possess antioxidant and anti-inflammatory activity. Platonin has been used to treat trauma, ulcers and some acute inflammations and it also reported to improve blood circulation and reduce mortality in endotoxin-induced rat models. Our previous studies established that platonin suppresses the lipopolysaccharides (LPS)-induced inflammatory cytokines, including interleukin-1β (IL-1β-+), IL-6, tumor necrosis factor-α (TNF-α), and inducible nitric oxide synthase (iNOS). Nuclear factor-kB (NF-kB) and activator protein-1 (AP-1) transcription factors are reported to be essential in mediating the endotoxin-induced production of inflammatory molecules. In vivo studies from our groups revealed that platonin has potential effects on inhibiting pyrogen release, tissue damage and ischemia during heatstroke, ischemia reperfusion injury in lungs and also improve the survival of skin allografts in rats. Clinically, this compound has been proven to cure juvenile rheumatoid arthritis (JRA) and polyarteritis nodosa (PN). In this review, we summarize the pharmacological and clinical effects of platonin via describing the potential molecular mechanism of regulation of inflammatory molecules of mitogen-activated protein kinases (MAPKs), including extracellular regulated kinase (ERK), c-jun N-terminal kinase (JNK), and p38 MAPK and also NF-kB activation. Moreover, this paper discusses the signaling pathways expedited by NF-kB, AP-1, MAPKs and NO/NOS, these all have been reflected in inflammatory processes, and could be the encouraging molecular targets for the design of pharmaceutical drugs targeting antiinflammatory therapy.

Gene delivery into cells offers opportunities to treat various human genetic diseases. Effective gene delivery is dependent on its stability and ability to transfect across cells. DNA is susceptible to enzymatic degradation and its negatively charge are barriers towards successful transfection. DNA has to be protected from degradation and neutralised. Non-viral vectors are preferred carrier systems, therefore, the use of cyclodextrins with Pluronic®-F127 and folic acid at different concentrations to stabilise the formulation was investigated. Formulations were characterised in fresh and freeze dried forms. DNA stability in formulations was tested by determining the stability of DNA against enzymatic degradation. Degree of DNA inclusion into cyclodextrins was investigated using fluorescence spectroscopy. Thermal behaviour was studied using Differential Scanning Calorimetry (DSC). Incorporation of Pluronic®-F127 produced most stable formulations regarding enzymatic degradation. These formulations show high percentage inclusion. Shift of peaks in FTIR data, appearance of uniform particulate as detected by SEM and changing in the denaturation temperature as demonstrated by DSC data for Pluronic®-F127 containing formulations confirm clear interaction between Pluronic®-F127 and cyclodextrin/ DNA complex. It was noted that γ-cyclodextrin provide better protection and inclusion compared to β-cyclodextrin. Pluronic®-F127 with cyclodextrins is a promising combination to improve stability.

Staphylococcus aureus is a leading causative agent in sepsis, endocarditis, and pneumonia. An emerging concept is that prognosis worsens when the infecting S. aureus strain has the capacity to not only colonize tissue as an extracellular pathogen, but to invade host cells and establish intracellular bacterial populations. In previous work, we identified host CDC42 as a central regulator of endothelial cell invasion by S. aureus. In the current work, we report that ML 141, a first-in-class CDC42 inhibitor, decreases invasion and resultant pathogenesis in a dose-dependent and reversible manner. Inhibition was found to be due in part to decreased remodeling of actin that potentially drives endocytic uptake of bacteria/fibronectin/integrin complexes. ML 141 decreased binding to fibronectin at these complexes, thereby limiting a key pathogenic mechanism used by S. aureus to invade. Structural analogs of ML 141 were synthesized (designated as the RSM series) and a subset identified that inhibit invasion through non-cytotoxic and non-bactericidal mechanisms. Our results support the development of adjunctive therapeutics targeting host CDC42 for mitigating invasive infection at the level of the host.

The activities of carnosine (β-alanyl-L-histidine), carnosine imidazole containing dipeptide based derivatives (N-acetylcarnosine, carcinine, homocarnosine) and a carnosine degrading enzyme (serum carnosinase (EC 3.4.13.20); [human tissue carnosinase (EC 3.4.13.3), CN2 (CNDP2)] ) activities have been discrepantly linked to neuropathophysiological processes. Approximately 82% of the U.S. population will experience normal age-related cognitive decline, as compared to the precipitous losses that are associated with dementing disorders. Interventions designed to promote health and function through everyday activity and specific pharmaco-nutritional therapeutic treatments may enhance brain plasticity in key regions that support executive function. Cognitive health is multidimensional cascade of functions. It encompasses an array of functions, including general intellectual ability, memory, language, allowing a person to interact effectively and appropriately with the environment. The risk factors for reduced physical and cognitive functions in elderly people, as identified in longitudinal studies, relate to comorbidities, critical care situations, physical and psychosocial health, environmental conditions, social circumstances, nutrition, and lifestyle. Depression and dementia are both common in older adults; cognitive functioning declines slightly with normal aging; depression itself can be associated with cognitive impairment and dementia. In this study the role of carnosine and related neuron specific naturally-occurring endogenous imidazole-containing dipeptide pharmacoperones (N-acetylcarnosine, carcinine) is revealed presently in a surprisingly large amounts in long-lived human tissues to correct conformational abnormalities leading to distinct neurodegeneration and age-related disease states, treating cognitive deficits, depression and intellectual disabilities. Carnosine serves as a physiological buffering agent and a metal ion (e.g., zinc and copper) chelator, endowed with ferroxidase type activity; possess anti-aging functions, and free-radical scavenging activity, is capable of delaying senescence and extending the life-span of cultured human fibroblasts; is able to kill transformed cells and protect cells against aldehydes and amyloid peptide fragment. Carnosine and carcinine exhibit a well-documented anti-glycating activity against the glycation of proteins, including low-density lipoproteins, glucose degradation products, esterase, histones. A tissue carnosine-degrading enzyme (CN2) colocalized with the activity of histidine decarboxylase to histamine neurons in the hypothalamic tuberomammillary nucleus (TMN) plays a key role in the neuro-transmission and neuroregulation roles of imidazole-containing based dipeptides. Carnosine released from skeletal muscle during exercise may be transported into TMN-histamine neurons and hydrolyzed. Timing of carnosine present in the chicken broth, the specific patented nutraceutical composition (Can-C PlusTM), 1% N-acetylcarnosine lubricant eye drops or 1% carcinine lubricant eye drops formulations are important targeting posology vehicles that are involved in many CNS functions through the central brain histamine system including the vision enhancement functions, physiological regulation of cognitive functions, arousal; anxiety; activation of the sympathetic nervous system; the stress-related release of hormones from the pituitary and of central aminergic neurotransmitters; antinociception; water retention and suppression of eating. The roles for the carnosine-stimulated/mediated neuronal histamine system are proposed as a danger and physiological response system active in protection from neurodegenerative diseases and in management of cognitive deficits, depression and intellectual disabilities.