Synthesis and pharmacochemical study of novel polyfunctional molecules combining anti-inflammatory, antioxidant, and hypocholesterolemic properties

We have designed and synthesized a series of novel molecules having a residue of a classical NSAID and an antioxidant moiety, both attached through amide bonds to a known nootropic structure, an L-proline, trans-4-hydroxy-L-proline or DL-pipecolinic acid residue. The compounds were found to retain anti-inflammatory and antioxidant activities, to acquire hypocholesterolemic action, and to possess a greatly reduced gastrointestinal toxicity. The novel molecules could find useful applications, among others, in slowing the progression or delaying the onset of neurodegenerative diseases.

Experimental hyperlipidemia and the effect of NSAIDs

The effects of ip administration of NSAIDs in experimentally induced hyperlipidemia in rats was studied. An isotonic solution of Triton WR1339 (tyloxapol) was administered ip to rats one hour after ip administration of the examined anti-inflammatory drug. After 24 h, blood was collected for the determination of plasma total cholesterol (TC), LDL and trigluceride (TG) concentrations. The NSAIDs used in our experimental model are selective or non selective COX-1 inhibitors as well as one non selective COX-2 inhibitor. Most of the drugs significantly reduced the TC, TG and LDL concentrations in the plasma of hyperlipidemic rats. While studies link atheromatosis to inflammation, our results potentially also link anti-inflammatory activity with hypolipidemia. Thus, NSAIDs not only may address the inflammatory aspect of atherosclerosis but also may contribute directly by inducing hypolipidemia.

Kinetics of antibody concentration and avidity for the assessment of immune response to pneumococcal vaccine among children with bone marrow transplants

The kinetics of the immune response to the 23-valent pneumococcal polysaccharide vaccine (PPV) were studied in 38 children who received bone marrow transplants (BMTs). Anti-pneumococcal antibody concentrations increased 1 and 3 months after vaccination for all 5 serotypes tested, but, in 21 children, the vaccine was not adequately immunogenic. Children vaccinated <18 months after receiving a BMT had a 4.2-fold increased odds of poor response (P=. 06). Antibody concentrations returned close to baseline levels 9 months after vaccination. Avidity declined significantly as early as 1 month after vaccination and remained low thereafter. Antibody concentration responses to PPV were superior among 9 healthy control children (P=.001); 37 of 38 children with a BMT elicited adequate, persistent immune responses to Haemophilus influenzae conjugate vaccine. Immune responses to PPV in children with a BMT are suboptimal, short lived, and associated with declining avidity. The different kinetics of antibody concentration and avidity indicate that both markers should be used for evaluating pneumococcal vaccines in this high-risk population.

Induction of a subgroup of acute phase protein genes in mouse liver by hyperthermia

We have demonstrated that two members of the acute phase reactant family of positively regulated genes, alpha 1-acid glycoprotein (AGP-1 and AGP-2) and C-reactive protein (CRP) are induced by hyperthermia, while two others, the serum amyloid A (SAA) and alpha 1-antitrypsin (AT) genes, are not. Albumin (ALB), a negative acute phase reactant gene, is also induced by hyperthermia. The AGP-1, AGP-2, and CRP genes require glucocorticoids, but not IL-6, IL-1 beta or TNF alpha in response to hyperthermia. As with LPS, the C/EBP beta mRNA levels increased, while the C/EBP alpha mRNA levels decreased in response to LPS. In contrast to the LPS response, C/EBP delta was unchanged. Protein pool levels and DNA-binding activities of the 35 and 20 kDa C/EBP beta isoforms increase, whereas protein pool levels of the 42 kDa C/EBP alpha decrease and the 30kDa remained high. These studies suggest that the synthesis of specific C/EBP alpha and C/EBP beta isoforms is induced by hyperthermia, and that the regulation of the AGP-1 and AGP-2 genes during heat stress may involve one of these isoforms. The difference between the responses to hyperthermia and LPS is that the former, may not involve the participation of cytokines. Furthermore, since cis-acting heat shock elements (HSE) are located in the promoter regions of the ALB, CRP, and C/EBP beta genes, these regulatory sequences may be involved in the in vivo activation of these genes by hyperthermia.

Regulation of cytokine gene expression by adjuvants in vivo

Antibody isotype affects biological activity of the antibodies and therefore should be considered in prevention of disease by vaccination. In previous reports, we demonstrated that adjuvants affect the antibody isotype switching process and favour the production of certain isotypes. The present study extends these findings and shows fundamental differences in the cytokine induction pattern according to the adjuvant used. Cytokine mRNA levels were determined by in situ RNA-RNA hybridization performed on splenocytes isolated from mice injected with different adjuvants. The results revealed that Freund's complete adjuvant (FCA), Freund's incomplete adjuvant (FIA), Al(OH)3 and QuilA administration results in a type-2 (humoral) response, increasing IL-4, IL-5 and IL-13 gene expression, while poly I:C exhibits a type-1 (cell-mediated) response, increasing the production of interferon-gamma (IFN-gamma), IL-2 and IL-6 mRNA. Finally, BeSO4 and poly A:U augment IL-5 and IL-6 mRNA production, while lipopolysaccharide (LPS) and LiCl augment IL-6 and tumour necrosis factor-alpha (TNF-alpha) mRNA production. Also, the adjuvants appear capable of overcoming the inherent IL-2/IFN-gamma and IL-4 dichotomy of C57B1/6 and BALB/c mice, respectively, in response to cellular antigens such as Leishmania and herpes simplex virus (HSV). The overall data suggest that adjuvants direct the isotype switching process via induction of certain cytokines, a finding that can be useful in selection of the most efficient isotype of protective antibodies for disease prevention by vaccination.

The anti-inflammatory effect of opioids

The anti-inflammatory activity of two novel opioids PM and PO as well as of pethidine was studied. The mouse paw edema, induced by various phlogistic agents, was significantly inhibited after the administration of opioids, fact that was independent of their antioxidant properties. The anti-inflammatory action of the above opioids was not reversed by naloxone. These results suggest that a variety of complex regulatory activities may be performed by opioid agonists via naloxone-sensitive or naloxone insensitive receptors on inflammatory cells, directly or indirectly by the inhibition of cytokines and mediators involved in inflammation.

Modulation of alpha 1-acid glycoprotein (AGP) gene induction following honey bee venom administration to adjuvant arthritic (AA) rats; possible role of AGP on AA development

Honey bee venom (HBV) administration to adjuvant arthritic (AA) rats resulted in a significant suppression of arthritis and in suppression of the hepatic acute phase alpha 1-acid glycoprotein (AGP) gene induction at the early stages of disease development. AGP administration in AA rats resulted in acceleration of arthritis development and in increase of severity and duration of the disease. IL-1, IL-6, tumour necrosis factor (TNF) and glucocorticoids alone are not responsible for the HBV-mediated AGP gene down-regulation. These results indicate that AGP gene expression in AA and HBV-treated AA rats involves the interaction of several factors, and that AGP plays a role for AA development in rats.