ACE/angiotensin-converting enzyme

Rescinnamine as a first lead in inducing MSH2-dependent cell death [1]
It has previously been shown that reserpine and rescinnamine are capable of inducing cell death in an MSH2-dependent manner (Vasilyeva 2009, 2010). Further experiments demonstrated that this indole alkaloid is capable of overcoming resistance to cisplatin in ovarian cancer cells (Fig. 1).

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Effects of rescinnamine analogs on cell viability [1]
We next tested these new rescinnamine analogs in a well-defined cellular system with an endometrial cell line deficient (HEC59) and proficient (via chromosome transfer, HEC59 + chr.2) for MSH2. This cell system allows to determine whether our new analogs hit their target and, generally, induce cell death. The assays identified a few compounds that induced cell killing in the micromolar range (Fig. 6 and Table 1, compounds 1, 6, 7, 13, 15 and to a lesser extent 12).

These initial results suggested that computational modeling of docking to a specific target protein can identify lead compounds that have specific characteristics. In our case, rescinnamine was identified to be a good lead toward the development of an effective cancer drug that targets a very specific, pro-apoptotic mechanism that is more prevalent in cancer cells. When applied to a xenograft model, however, the hypotensive activity of the drug prevented administration of statistically effective doses, though a significant trend toward tumor inhibition is observed (Fig. 2). Since none of the commercially available reserpine analogs showed much promise in inducing MSH2-dependent cell death (Vasilyeva et al., 2010), we engaged computational modeling and chemical synthesis to generate novel rescinnamine analogs [2].

Cell Biology [1]
HEC59 cells (msh2 deficient) and the paired cell line HEC59 chr. 2 that restores the MSH2-deficiency via chromosome transfer have been extensively characterized (Umar et al., 1997). Cells were grown in standard growth media (DMEM-F12 + 10% FBS). Cells were plated in microtiter plates at an appropriate concentration in 100 µl media and incubated overnight. Media was replaced with media containing drug and allowed to incubate for 24 hours at indicated concentrations. Untreated cells received fresh media with vehicle only. One solution reagent (CellTiter 96)(r) Aqueous One Solution) was added to existing media (20 µl/well) and allowed to incubate 3–4 hrs. A plate reader was used to record the absorbance at 490 nm. Assays were performed at least in triplicates. Cell viability at each concentration was analyzed for IC50 values using GraphPad Prism 4™. Graphs represent mean values and standard deviations.

Xenograft [1]
SW416 or HEC59 cells in PBS mixed with Matrigel (1:1; BD Biosciences) were subcutaneously injected into the flank of nude donor mice. Tumors were grown for up to 3 weeks. Mice were euthanized, tumors excised, minced into 3 mm pieces, and surgically implanted into the right flank of acceptor mice (10 per group). Isoflurane anesthesia was provided during tumor inoculation. Injection of compounds was started 3 days following tumor implantation to allow recovery from surgery. Compounds were given intraperitoneally, in a volume of 0.5 ml/mouse with a ¼ inch, 23-gauge needle in a 6 ml plastic syringe. Mice were monitored based on survival and body weight. Tumor size, measured by caliper, and body weight were monitored daily for 57 days, and the prolongation of median survival time after ip treatment determined. Any animals showing signs of distress, unnatural movements, severe loss of appetite, severe signs of hypotension, tumor size of 1000g, or weight loss exceeding 10% before the end of the study were euthanized. Tumors were measured twice a week for each group. Tumor volume is calculated as length (mm) x width (mm)2. Initial measurements were performed when the tumor reached 150–200 mg. Tumor weight (in mg) is calculated as tumor weight (mg) - (length(mm) of tumor x width (mm) of tumor2)/2.

Absorption, Distribution and Excretion
Rauvoline is readily absorbed from the gastrointestinal tract and injection site. See Rauvoline. ...It can cross the placental barrier and may affect the newborn. /Rauvoline/

Human TDLo oral 4 ug/kg/D Sensory organs and special senses: Other changes: olfaction; Behavior: somnolence (overall activity inhibition); Behavioral science: Antipsychotics and Chemicals Toxicology, Deichmann, WB, New York, Academic Press, 1969, -(517), 1969
Rats oral LD50 1 gm/kg Japanese Medicine, 6(898), 1982
Rats intraperitoneal LD50 250 mg/kg Japanese Medicine, 6(898), 1982
Rats subcutaneous LD50 540 mg/kg Japanese Medicine, 6(898), 1982
Mice oral LD50 1420 mg/kg Psychotropic Drugs and Related Compounds, Second Edition, Usdin, E. and DH Efron, Washington, D.C., 1972, -(109), 1972

[1]. Computational and synthetic studies towards improving rescinnamine as an inducer of MSH2-dependent apoptosis in cancer treatment. Mol Cancer Biol. 2013;1(1):44.

[2]. Pharmacological studies with rescinnamine, a new alkaloid isolated from Rauwolfia serpentina. Proc Soc Exp Biol Med. 1954 May;86(1):120-4.

Rescinnamine is an odorless white to milky white crystalline powder. (NTP, 1992)
Rescinnamine is a methyl ester belonging to the organic heteropentane compound and indole alkaloids. It is an antihypertensive drug. It is derived from the hydride of yohimbine.
Rescinnamine is an angiotensin-converting enzyme inhibitor used as an antihypertensive drug. It is an alkaloid extracted from Rauwolfia serpentina and other Rauwolfia species.
Rescinnamine has been reported to be found in Rauwolfia species, Rauwolfia serpentina, and other organisms with relevant data.
Drug Indications
For the treatment of hypertension.
Mechanism of Action
Rescinnamine binds to and inhibits the activity of angiotensin-converting enzyme. Rescinnamine competitively binds to angiotensin-converting enzyme with angiotensin I, thereby blocking the conversion of angiotensin I to angiotensin II. ACE inhibition leads to a decrease in plasma angiotensin II levels. Because angiotensin II is a vasoconstrictor and a negative feedback regulator of renin activity, a decrease in its concentration leads to a drop in blood pressure and stimulates baroreceptor reflex mechanisms, resulting in decreased vasopressor activity and reduced aldosterone secretion.
See Rauvolfia alkaloids.
...By blocking the afferent impulses stimulating the sympathetic vasopressor reflex near the hypothalamus, and/or by reducing the reactivity of the peripheral sympathetic nervous system through depletion of norepinephrine at nerve endings, it leads to varying degrees of reduction in mean arterial blood pressure. /Rauvolfia.../
See Rauvolfia alkaloids. It also exhibits non-hypnotic sedative effects, which may be related to its ability to regulate serotonin and/or norepinephrine concentrations in the brainstem. /Rauvolidine/

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Therapeutic Uses
Oral administration…It has little therapeutic value for severe hypertension and hypertension associated with preeclampsia unless used in combination with thiazide compound preparations or more potent antihypertensive drugs…/Rauvolidine/
Antihypertensive drugs/SRP: Widely replaced by more effective therapies/
Sedatives/SRP: Widely replaced by more effective therapies/

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Drug Warnings
Symptoms may worsen in patients with allergic diseases./Rauvolidine/
It has antihypertensive and sedative effects accompanied by bradycardia, but has no significant effect on cardiac output and renal plasma flow. Rauvolidine compounds
Except for the lower frequency and milder severity of sedation and bradycardia caused by lysineamine, the incidence of other side effects (such as asthenia, fatigue, nasal congestion, dizziness, confusion, increased appetite, and weight gain) is roughly the same as that of toxapine.
Unless the dosage is carefully adjusted, this drug may induce paradoxical anxiety and adverse reaction depression. ...Suicidal depression is the most serious adverse reaction. ...Caution should be exercised in patients with a history of peptic ulcer disease. ...Contraindicated in women with eclampsia and during lactation... /Risapine/
For more complete data on drug warnings for Risapine (11 in total), please visit the HSDB record page.

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Pharmacodynamics
Used to treat hypertension. Risapine inhibits angiotensin-converting enzyme (ACE). ACE is a peptidyl dipeptidase that catalyzes the conversion of angiotensin I to the vasoconstrictor angiotensin II. Angiotensin II also stimulates the adrenal cortex to secrete aldosterone and causes vasoconstriction, both of which lead to increased vascular resistance. By inhibiting angiotensin II, the reabsorption of aldosterone and vasoconstriction are reduced. This combined effect helps lower blood pressure.

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We and other researchers have previously demonstrated that mismatch repair proteins, in addition to their repair functions, are involved in initiating cell death. Certain drugs can induce this cell death activity, and this activity is independent of the protein's repair function. Reserpine, a derivative of reserpine (a drug used decades ago to treat hypertension), has been shown to target the cell death initiation activity of mismatch repair proteins. However, in animal studies, the drug’s antihypertensive effect prevented it from reaching statistically significant tumor shrinkage concentrations. We investigated the structural modification methods of reserpine and their effects on cell survival by combining computational modeling, chemical synthesis, and cell experiments. These results provide a basis for further computational modeling to screen for new synthetic lead compounds for subsequent biological testing. [1]

C35H42N2O9

634.726

634.289

C, 66.23; H, 6.67; N, 4.41; O, 22.69

24815-24-5

5280954

Fine needles from benzene
WHITE, OR PALE BUFF TO CREAM-COLORED CRYSTALLINE POWDER

1.31g/cm3

756.8ºC at 760 mmHg

238ºC

411.5ºC

8.5E-23mmHg at 25°C

1.621

4.508

1

10

11

46

1080

6

COC1=CC2=C(C=C1)C3=C([C@H]4C[C@H]5[C@H](C[C@H]([C@@H]([C@H]5C(=O)OC)OC)OC(=O)/C=C/C6=CC(=C(C(=C6)OC)OC)OC)CN4CC3)N2

SZLZWPPUNLXJEA-QEGASFHISA-N

InChI=1S/C35H42N2O9/c1-40-21-8-9-22-23-11-12-37-18-20-15-29(46-30(38)10-7-19-13-27(41-2)33(43-4)28(14-19)42-3)34(44-5)31(35(39)45-6)24(20)17-26(37)32(23)36-25(22)16-21/h7-10,13-14,16,20,24,26,29,31,34,36H,11-12,15,17-18H2,1-6H3/b10-7+/t20-,24+,26-,29-,31+,34+/m1/s1

methyl (1R,15S,17R,18R,19S,20S)-6,18-dimethoxy-17-[(E)-3-(3,4,5-trimethoxyphenyl)prop-2-enoyl]oxy-1,3,11,12,14,15,16,17,18,19,20,21-dodecahydroyohimban-19-carboxylate

Anaprel; Apoterin; Apoterin S; Rescinnamine; CCRIS-4711; Cartric; CCRIS 4711; CCRIS4711; Cinnaloid; Cinnasil; Moderil; Rescisan; Resealoid; Reserpinine; Scinnamina

2934.99.9001

Powder      -20°C    3 years

                     4°C     2 years

In solvent   -80°C    6 months

                  -20°C    1 month

Room temperature (This product is stable at ambient temperature for a few days during ordinary shipping and time spent in Customs)

May dissolve in DMSO (in most cases), if not, try other solvents such as H2O, Ethanol, or DMF with a minute amount of products to avoid loss of samples

Note: Listed below are some common formulations that may be used to formulate products with low water solubility (e.g. < 1 mg/mL), you may test these formulations using a minute amount of products to avoid loss of samples.

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Injection Formulation 1: DMSO : Tween 80： Saline = 10 : 5 : 85 (i.e. 100 μL DMSO stock solution → 50 μL Tween 80 → 850 μL Saline)
*Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH ₂ O to obtain a clear solution.
Injection Formulation 2: DMSO : PEG300 ：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL DMSO → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline)
Injection Formulation 3: DMSO : Corn oil = 10 : 90 (i.e. 100 μL DMSO → 900 μL Corn oil)
Example: Take the Injection Formulation 3 (DMSO : Corn oil = 10 : 90) as an example, if 1 mL of 2.5 mg/mL working solution is to be prepared, you can take 100 μL 25 mg/mL DMSO stock solution and add to 900 μL corn oil, mix well to obtain a clear or suspension solution (2.5 mg/mL, ready for use in animals).

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Injection Formulation 4: DMSO : 20% SBE-β-CD in saline = 10 : 90 [i.e. 100 μL DMSO → 900 μL (20% SBE-β-CD in saline)]
*Preparation of 20% SBE-β-CD in Saline (4°C，1 week): Dissolve 2 g SBE-β-CD in 10 mL saline to obtain a clear solution.
Injection Formulation 5: 2-Hydroxypropyl-β-cyclodextrin : Saline = 50 : 50 (i.e. 500 μL 2-Hydroxypropyl-β-cyclodextrin → 500 μL Saline)
Injection Formulation 6: DMSO : PEG300 : castor oil : Saline = 5 : 10 : 20 : 65 (i.e. 50 μL DMSO → 100 μLPEG300 → 200 μL castor oil → 650 μL Saline)
Injection Formulation 7: Ethanol : Cremophor : Saline = 10： 10 : 80 (i.e. 100 μL Ethanol → 100 μL Cremophor → 800 μL Saline)
Injection Formulation 8: Dissolve in Cremophor/Ethanol (50 : 50), then diluted by Saline
Injection Formulation 9: EtOH : Corn oil = 10 : 90 (i.e. 100 μL EtOH → 900 μL Corn oil)
Injection Formulation 10: EtOH : PEG300：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL EtOH → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline)

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Oral Formulation 1: Suspend in 0.5% CMC Na (carboxymethylcellulose sodium)
Oral Formulation 2: Suspend in 0.5% Carboxymethyl cellulose
Example: Take the Oral Formulation 1 (Suspend in 0.5% CMC Na) as an example, if 100 mL of 2.5 mg/mL working solution is to be prepared, you can first prepare 0.5% CMC Na solution by measuring 0.5 g CMC Na and dissolve it in 100 mL ddH2O to obtain a clear solution; then add 250 mg of the product to 100 mL 0.5% CMC Na solution, to make the suspension solution (2.5 mg/mL, ready for use in animals).

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Oral Formulation 3: Dissolved in PEG400
Oral Formulation 4: Suspend in 0.2% Carboxymethyl cellulose
Oral Formulation 5: Dissolve in 0.25% Tween 80 and 0.5% Carboxymethyl cellulose
Oral Formulation 6: Mixing with food powders

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Note: Please be aware that the above formulations are for reference only. InvivoChem strongly recommends customers to read literature methods/protocols carefully before determining which formulation you should use for in vivo studies, as different compounds have different solubility properties and have to be formulated differently.

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 (Please use freshly prepared in vivo formulations for optimal results.)