[Herpes Zoster Ophthalmicus after Pfizer BNT162b2 and Moderna mRNA-1273 vaccination in two young and immunocompetent patients]. / Zona ophtalmique après vaccination par Pfizer BNT162b2 et Moderna mRNA-1273 chez deux patients jeunes et immunocompétents.

Coronavirus disease 19 (COVID-19) was first observed in Wuhan, China. The disease is caused by a virus (SARS-CoV-2), which spread around the world within a matter of weeks, leading to a large number of deaths. While the health crisis was managed on the ground, the scientific community focused on finding a means to stop it. Vaccine candidates such as the mRNA vaccines (Pfizer BTN162b2 and Moderna mRNA-1273), started to emerge. As these treatments came on the market recently, there is still concern about potential side effects, among them, Herpes Zoster Ophthalmicus (HZO).

RGDS and DGEA-induced [Ca2+]i signalling in human dermal fibroblasts.

A pulse of short peptides, RGDS and DGEA in the millimolar range, immediately elicits in normal human fibroblasts a transient increase of intracellular Ca2+ ([Ca2+]i). In the present study, we show that this [Ca2+]i occurs in an increasing number of cells as a function of peptides concentration. It is specific of each peptide and inhibited at saturating concentration of the peptide in the culture medium. The [Ca2+]i transient depends on signalling pathways slightly different for DGEA and RGDS involving tyrosine kinase(s) and phosphatase(s), phospholipase C, production of inositol-trisphosphate and release of Ca2+ from the cellular stores. GFOGER, the classical collagen binding peptide of alpha1- alpha2- and alpha11-beta1 integrins, in triple helical or denatured form, does not produce any Ca2+ signal. The [Ca2+]i signalling induced by RGDS and DGEA is inhibited by antibodies against beta1 integrin subunit while that mediated by RGDS is also inhibited by antibodies against the alpha3 integrin. Delay in the acquisition of responsiveness is observed during cell adhesion and spreading on a coat of fibronectin for RGDS or collagen for DGEA or on a coat of the specific integrin-inhibiting antibodies but not by seeding cells on GFOGER or laminin-5. This delay is suppressed specifically by collagenase acting on the collagen coat or trypsin on the fibronectin coat. Our results suggest that free integrins and associated focal complexes generate a Ca2+ signal upon recognition of DGEA and RGDS by different cellular pathways.

[Flavonoid and dianthranoid levels of the St.-John's-wort flowering tops]. / Teneurs en flavonoïdes et en dianthranoïdes de la sommité fleurie de millepertuis.

Dried flowering tops of Hypericum perforatum L. (16 batches) and H. maculatum (3 batches) were studied according to the harvest period. The mean levels of the flavonoid and dianthranoid compounds were respectively: total flavonoids 3.20 and 3.92%, hyperoside 0.87 and 2. 12%, rutin 0.54 and 0.02%, isoquercitrin 0.48 and 0.75%; total dianthranoids 0.14 and 0.13%, hypericin 0.04 and 0.02%, pseudohypericin 0.08 and 0.11%. The flavonoid and dianthranoid levels were higher in young flowering tops of H. perforatum. 3 commercial batches were also examined for a comparative study. Pharmacopoeial specifications are proposed for a revision of the monograph "St.-John's-wort".

Synthesis and biological evaluation of bombesin constrained analogues.

Analogues of bombesin which incorporate dipeptide or turn mimetics have been synthesized. One of them (compound 11) containing a seven-membered lactam ring revealed a good affinity for GRP/BN receptors on rat pancreatic acini (K(i) value of 1.7 +/- 0.4 nM) and on Swiss 3T3 cells (K(i) value of 1.0 +/- 0.2 nM). On the basis of this observation, antagonists containing the same dipeptide mimic were obtained by modification of the C-terminal part of the bombesin analogues. The most potent constrained compounds (15 and 17) were able to antagonize 1 nM bombesin-stimulated amylase secretion from rat pancreatic acini with high potency (K(i) = 21 +/- 3 and 3.3 +/- 1.0 nM, respectively) and 10(-7) M bombesin-stimulated ¿(3)Hthymidine incorporation into Swiss 3T3 cells (K(i) = 7.8 +/- 2. 0 and 0.5 +/- 0.1 nM, respectively).

Synthesis and biological evaluation of bradykinin B(1)/B(2) and selective B(1) receptor antagonists.

We recently described a potent bradykinin B(2) receptor agonist (JMV1116) obtained by replacing the D-Tic-Oic dipeptide moiety of HOE140 by a (3S)-amino-5-(carbonylmethyl)-2,3-dihydro-1, 5-benzothiazepin-4(5H)-one (D-BT) moiety. This compound inhibited the specific binding of [(3)H]BK on membranes of CHO cells expressing the human cloned B(2) receptor with nanomolar affinity and contracted both isolated rat uterus and human umbilical vein. These data demonstrated that D-BT could be a good mimic of the Pro-Phe dipeptide. In the present study we characterized B(1) receptor antagonists containing the D-BT moiety. We prepared an analogue of compound JMV1116 deleting the C-terminal arginine residue. The resulting compound (1) had an affinity of 83 nM for the human cloned B(1) receptor. The most remarkable property of 1 is its ability to bind also the B(2) receptor with an affinity of 4.4 nM despite the absence of the C-terminal arginine residue. Modifications at the N-terminal part of 1 associated with the substitution of the thienylalanine residue by alpha-(2-indanyl)glycine resulted in analogues selectively binding to the B(1) receptor with an affinity in the picomolar range.

A rational approach to the design and synthesis of a new bradykinin B(1) receptor antagonist.

We have previously synthesized a potent and selective B(1) bradykinin receptor antagonist, JMV1645 (H-Lys-Arg-Pro-Hyp-Gly-Igl-Ser-D-BT-OH), containing a dipeptide mimetic ((3S)-amino-5-carbonylmethyl-2,3-dihydro-1, 5-benzothiazepin-4(5H)-one (D-BT) moiety) at the C-terminal. Analogues of this potent B(1) bradykinin receptor antagonist in which the central Pro(2)-Hyp(3)-Gly(4)-Igl(5) tetrapeptide has been replaced by constrained N-1-substituted-1,3,8-triazaspiro¿4. 5decan-4-one ring system were synthesized. Among these analogues, compound JMV1640 (1) was found to have an affinity of 24.10 +/- 9.48 nM for the human cloned B(1) receptor. It antagonized the ¿des-Arg(10)-kallidin-induced contraction of the human umbilical vein (pA(2) = 6.1 +/- 0.1). Compound 1 was devoid of agonist activity at the kinin B(1) receptor. Moreover, it did not bind to the human cloned B(2) receptor. Therefore, JMV1640 constitutes a lead compound for the rational search of nonpeptide B(1) receptor analogues based on the BK sequence.

Identification of synthetic by-products in combinatorial libraries using high performance liquid chromatography-electrospray ionization mass spectrometry.

High performance liquid chromatography (HPLC), electrospray ionization mass spectrometry (ESI) and high performance liquid chromatography coupled to mass spectrometry (LC-MS) were used to analyze randomly chosen samples from parallel syntheses carried out on derivatized polypropylene crowns compatible with a Multipin solid support system. Side-reactions and by-products were clearly identified, and the yields of the expected molecules were unexpectedly low for most samples. LC-MS was superior to HPLC with absorbance detection or electrospray mass spectrometry alone for determining the identity and purity of each desired combinatorial compounds.

Design and synthesis of potent bradykinin agonists containing a benzothiazepine moiety.

A bradykinin analogue (H-Arg-Pro-Pro-Gly-Phe-Ser-D-BT-Arg-OH, 3) in which the Pro-Phe dipeptide was replaced by the (3S)[amino]-5-(carbonylmethyl)-2,3-dihydro-1, 5-benzothiazepin-4(5H)-one (D-BT) moiety has been synthesized. The same modification was performed on the potent bradykinin B(2) receptor antagonist HOE 140 (H-D-Arg-Arg-Pro-Hyp-Gly-Thi-Ser-D-Tic-Oic-Arg-OH), in which the -D-Tic-Oic- moiety was replaced by D-BT to yield H-D-Arg-Arg-Pro-Hyp-Gly-Thi-Ser-D-BT-Arg-OH, 1 (JMV1116). These compounds were examined in vitro for their binding affinity toward bradykinin B(1) and B(2) receptors as well as for their ability to interfere with bradykinin-induced contraction of both human umbilical vein and rat uterus. The two compounds 3 and 1 competed with [(3)H]bradykinin binding to the human cloned B(2) receptor giving K(i) values of 13 +/- 2 and 0.7 +/- 0.1 nM, respectively. Unexpectedly, both compounds were full bradykinin B(2) receptor agonists on the human umbilical vein (pD(2) = 6.60 +/- 0.07 for 3 and 6.80 +/- 0.08 for 1) and rat uterus (pD(2) = 7.20 +/- 0.09 for 3 and 7.50 +/- 0.09 for 1) preparations with the same efficacy as bradykinin. In addition 1 induced a concentration-dependent phosphoinositide production in CHO cells expressing the human cloned B(2) receptor. These data provide evidence for a bioactive conformation of bradykinin constrained at the dipeptide Pro-Phe.

Synthesis and characterization of bradykinin B(2) receptor agonists containing constrained dipeptide mimics.

We have previously shown that substitution of the D-Tic-Oic dipeptide by a (3S)-[amino]-5-(carbonylmethyl)-2,3-dihydro-1, 5-benzothiazepin-4(5H)-one (D-BT) moiety in the bradykinin B(2) receptor antagonist HOE 140 resulted in a full potent and selective bradykinin B(2) receptor agonist (H-DArg-Arg-Pro-Hyp-Gly-Thi-Ser-D-BT-Arg-OH, JMV1116) exhibiting a high affinity for the human receptor (K(i) 0.7 nM). In the present study, we have investigated the effects of replacement of the D-Tic-Oic moiety by various constrained dipeptide mimetics. The resulting compounds were tested for their binding affinity toward the cloned human B(2) receptor and for their functional interaction with the bradykinin-induced contraction of isolated human umbilical vein. Subsequently, we have designed novel bradykinin B(2) receptor agonists which are likely to be resistant to enzymatic cleavage by endopeptidases and which might represent interesting new pharmacological tools. In an attempt to increase the potency of compound JMV1116, both its N-terminal part and the D-BT moiety were modified. Substitution of the D-arginine residue by a L-lysine residue led to a 10-fold more potent bradykinin B(2) ligand [compound 22 (JMV1465) (K(i) 0.07 nM)], retaining full agonist activity on human umbilical vein. Substitution of the D-BT moiety by a (3S)-[amino]-5-(carbonylmethyl)-2,3-dihydro-8-methyl-1, 5-benzothiazepin-4(5H)-one [D-BT(Me)] moiety led to compound 23 (JMV1609) which exhibited a higher agonist activity (pD(2) = 7.4) than JMV1116 (pD(2) = 6.8).

Some of the amino acid chemistry going on in the Laboratory of Amino Acids, Peptides and Proteins.

Some of the chemistry of amino acids going on in our laboratory (Laboratoire des Amino acides Peptides et Protéines) is described as well as some mass spectrometry methodology for their characterization particularly on solid supports. Several aspects are presented including: (i) the stereoselective synthesis of natural and unnatural amino acids using 2-hydroxypinan-3-one as chiral auxiliary; (ii) the stereoselective synthesis of natural and unnatural amino acids by deracemization of alpha-amino acids via their ketene derivatives; (iii) the synthesis of alpha-aryl-alpha-amino acids via reaction of organometallics with a glycine cation; (iv) the diastereoselective synthesis of glycosyl-alpha-amino acids; (v) the synthesis of beta-amino acids using alpha-aminopyrrolidinopiperazinediones as chiral templates; (vi) the reactivity of urethane-N-protected N-carboxyanhydrides. To characterize natural and non natural amino acids through their immonium ions by mass spectrometry, some methodology is also described.

JMV1155: a novel inhibitor of glycine-extended progastrin-mediated growth of a human colon cancer in vivo.

BACKGROUND: Glycine-extended progastrin (G-17-Gly), the immediate biosynthetic precursor to gastrin (G-17), stimulates growth of some gastrointestinal cancers in vitro. The purpose of this study was twofold: to evaluate the effects of G-17-Gly on a human colon cancer (DLD-1) in vivo and to determine whether the novel gastrin-receptor antagonist, JMV1155, inhibits G-17-Gly-mediated growth. METHODS: DLD-1 cells (2 x 10(6)) were injected subcutaneously (s.c.) at a single site in athymic nude mice. Mice were randomized to four groups (n = 6/group) to receive injections, s.c., tid of either saline (control), G-17-Gly, JMV1155, or G-17-Gly + JMV1155 for 28 days. Tumors were measured biweekly until sacrifice at which time tumors were weighed and analyzed for DNA and protein content. RESULTS: JMV1155 significantly inhibited G-17-Gly-stimulated growth of DLD-1 tumors by 14 days of treatment, producing a 56% decrease in tumor size by 28 days. JMV1155 also significantly decreased G-17-Gly-mediated increases in tumor weight (by 64%), DNA content (by 61%), and protein content (by 65%). CONCLUSIONS: We have demonstrated, for the first time, that the novel gastrin-receptor antagonist, JMV1155, blocks G-17-Gly-induced growth of a transplanted human colon cancer in vivo. Hormonally based therapy with JMV1155 potentially could be employed for some patients with colon carcinoma.

Synthesis and pharmacological evaluation of dimer derivatives of the bradykinin receptor antagonist HOE-140.

The synthesis and pharmacological evaluation of dimer derivatives of the C-terminal fragments of the potent bradykinin antagonist HOE-140, linked through their N-termini, were performed. The influence of peptide moiety length was studied using the succinyl moiety as a linker. Our attention focused on the dimer of the C-terminal tetrapeptide of HOE-140 (compound JMV 980), which displayed some inhibiting activity (IC50 = 247 nM) for bradykinin B2 receptors. Unexpectedly, it was orally active in inhibiting bradykinin-induced hypotension in the rat. Based on this tetrapeptide dimer model, we synthesized pseudotetrapeptide dimer bradykinin antagonists 29 and 33, which exhibited high affinity (Ki = 76 and 61 nM, respectively) for the human cloned B2 receptor. In addition, compound 29 inhibited bradykinin-induced contraction of the human umbilical vein giving a pKB value of 6.45. Compounds 29 and 33 were selective toward B2 receptors because they did not bind to the cloned human B1 receptor up to 10 microM.

The use of N-urethane-protected N-carboxyanhydrides (UNCAs) in amino acid and peptide synthesis.

N-Urethane-protected N-carboxyanhydrides (UNCAs) are very reactive amino acid derivatives. They have been successfully used in peptide synthesis, in both solution and solid phase. We have demonstrated that UNCAs are interesting starting materials for the synthesis of various amino acid derivatives. Chemoselective reduction of UNCAs with sodium borohydride led the corresponding N-protected beta amino alcohols. Reaction of UNCAs with Meldrum's acid, followed by cyclisation, yielded enantiomerically pure tetramic acid derivatives. Diastereoselective reduction of tetramic acid derivatives produced [4S,5S)-N-alkoxycarbonyl-4-hydroxy-5-alkylpyrrolidin-2-ones derived from amino acids, which after hydrolysis yielded statine and statine analogues. Tetramic acid derivatives could also be obtained by reaction of UNCAs with benzyl ethyl malonate in the presence of sodium hydride to yield gamma-N-benzyloxycarbonylamino-beta-oxodicarboxyl esters followed by hydrogenolytic deprotection and decarboxylation. UNCAs also reacted with phosphoranes to produce the ketophosphorane in excellent yields. Subsequent oxidation with oxone or with [bis(acetoxy)-iodo]-benzene produced vicinal tricarbonyl derivatives. These reactions usually proceeded smoothly and with high yields.

Behavioral effects of the cyclic cholecystokinin peptide analogue JMV-320.

The in vivo effects of JMV-320 (a highly selective CCKB receptor ligand) and of CCK-4 on exploratory activity and memory in rats were compared. JMV-320 and CCK-4 did not modulate exploratory activity in an open field test but decreased it in an elevated plus-maze. CCK-4 (50 micrograms/kg) impaired passive avoidance response 3 h after training and JMV-320 (1 and 10 micrograms/kg) decreased active avoidance response 24 h after training. The behavioral effects of JMV-320 resemble the effects of CCK-4 and suggest that in vivo JMV-320 acts as a CCKB receptor agonist.

Synthesis and biological evaluation of cholecystokinin analogs in which the Asp-Phe-NH2 moiety has been replaced by a 3-amino-7-phenylheptanoic acid or a 3-amino-6-(phenyloxy)hexanoic acid.

Boc-Tyr(SO3H)-Nle-Gly-Trp-Nle-Asp-2-phenylethyl ester (JMV180), an analog of the C-terminal octapeptide of cholecystokinin (CCK-8), shows interesting biological activities behaving as an agonist at the high-affinity CCK binding sites and as an antagonist at the low-affinity CCK binding sites in rat pancreatic acini. Although we did not observe any major hydrolysis of the ester bond of Boc-Tyr(SO3H)-Nle-Gly-Trp-Nle-Asp-2-phenylethyl ester in our in vitro studies, we were aware of a possible and rapid cleavage of this ester bond during in vivo studies. To improve the stability of Boc-Tyr(SO3H)-Nle-Gly-Trp-Nle-Asp-2-phenylethyl ester, we decided to synthesize analogs in which the ester bond would be replaced by a carba (CH2-CH2) linkage. We synthesized the 3-amino-7-phenylheptanoic acid (beta-homo-Aph) with the R configuration in order to mimic the Asp-2-phenylethyl ester moiety and the 3-amino-6-(phenyloxy)hexanoic acid (H-beta-homo-App-OH), an analog of H-beta-homo-Aph-OH in which a methylene group has been replaced by an oxygen. (R)-beta-Homo-Aph and (R)-H-beta-homo-App-OH were introduced in the CCK-8 sequence to produce Boc-Tyr(SO3H)-Nle-Gly-Trp-Nle-(R)-beta-homo-Aph-OH and Boc-Tyr(SO3H)-Nle-Gly-Trp-Nle-(R)-beta-homo-App-OH. Both compounds were able to recognize the CCK receptor on rat pancreatic acini (IC50 = 12 +/- 8 nM and 13 +/- 5 nM, respectively), on brain membranes (IC50 = 32 +/- 2 nM and 57 +/- 5 nM, respectively), and on Jurkat T cells (IC50 = 75 +/- 15 nM and 65 +/- 21 nM, respectively). Like Boc-Tyr(SO3H)-Nle-Gly-Trp-Nle-Asp-2-phenylethyl ester, both compounds produced maximal stimulation of amylase secretion (EC50 = 6 +/- 2 nM and 4 +/- 2 nM, respectively) with no decrease of the secretion at high concentration indicating that these compounds probably act as agonists at the high-affinity peripheral CCK-receptor and as antagonists at the low-affinity CCK-receptor. Replacing the tryptophan by a D-tryptophan in such analogs produced full CCK-receptor antagonists. All these analogs might be more suitable for in vivo studies than Boc-Tyr(SO3H)-Nle-Gly-Trp-Nle-Asp-2-phenylethyl ester.

[Structure-activity relationship of cystokinins: analogs exhibiting selective activity]. / Relations structure-activité de la cholécystokinine: analogues présentant des activités sélectives.

Structure-activity relationship on cholecystokinin is presented. C-terminal heptapeptide analogues of cholecystokinin exhibiting selective agonist or antagonist activities were synthesized and their biological and pharmacological properties studied. We showed that: 1) Suppression of the C-terminal phenylalanine residue leads to peripheral as well as central cholecystokinin receptor antagonists; 2) Suppression of the C-terminal amide function produces "partial agonists" exhibiting interesting biological and pharmacological activities; 3) Replacement of L-tryptophan residue by D-tryptophan in such "partial agonist analogues" resulted in potent CCK receptor antagonists; 4) The peptide bond between methionine28 and glycine29, as well as the glycine residue are quite significant for the central biological activity; 5) It is possible to obtain highly potent and selective CCK analogues for the central receptor (CCK-B) by cyclization including the C-terminal tetrapeptide. Synthesis and pharmacological studies with these analogues have allowed to precise the significance of some amino acid residues as well as of some peptide bonds. They are significant pharmacological tools for the study of CCK-A (peripheral) and CCK-B (central) receptors, their biological actions and their associated intracellular messengers.

Cyclic cholecystokinin analogues that are highly selective for rat and guinea pig central cholecystokinin receptors.

Cholecystokinin (CCK) analogues (JMV310, JMV320, JMV328, and JMV332), obtained by side chain to side chain cyclization of a lysine residue in position 28 with a lysine residue in position 31, were found to be highly selective for the brain CCK receptor (CCK-B receptor), both in guinea pig and rat. In these analogues, the C-terminal tetrapeptide region of the molecule, which is the crucial determinant for binding to CCK-B receptors, has been constrained by cyclization. These analogues were highly potent in inhibiting binding of labeled CCK-8 to rat and guinea pig brain membranes (apparent affinity in the nanomolar range) but were poorly efficacious in inhibiting binding of labeled CCK-8 to rat or guinea pig pancreatic acini. In agreement with their low affinity for the pancreatic receptor, these CCK analogues were not very potent in stimulating amylase secretion. These cyclic CCK analogues were demonstrated to be highly selective for the brain CCK receptors.

Synthesis of cyclic analogues of cholecystokinin highly selective for central receptors.

Cyclic CCK analogues in which positions 28 and 31 have been replaced by lysine residues and whose side chains are bridged by a succinic moiety, were synthesized. They were tested for their ability to inhibit the binding of 125I-BH-CCK-8 to isolated rat pancreatic acini and to guinea pig brain membranes. These cyclic CCK-analogues were compared to the potent CCK analogue Boc-[Nle28,31]-CCK-7 and to Boc-Trp-Leu-Asp-Phe-NH2, analogue of CCK-4. These cyclic compounds appeared to be highly selective for central CCK receptors.